TIGSource Forums

(http://i.imgur.com/QXCkT8y.jpg)

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While I don't have money for anything right now, the incredibly cheap price of the Pi has made it seem at least like possible prospect of the future.

In the meantime, it would be fun to hear people talk about it. Your own experiences and projects, and projects of others that you think are cool.

Because I feel I want one simply because it's so easy to get (due to being cheap), but something's telling me I wouldn't really need it for anything, necessarily, so I might need to be taken down a few notches. :P

And it's a really interesting subject, anyhow!

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For those who don't know what it is:

It's a tiny computer with all the basic necessities (depending on model, but the latest seems to have a quad core processor, a decent GPU, 1GB of RAM, four USB ports, an ethernet port, headphone port, HDMI port and more) to get it up and running like a regular computer quite easily — perhaps installing Linux as the OS. Storage seems to be SD cards primarily.

There are also add-ons made specifically for the Pi. It has been used to make game consoles, cameras, robot kits (think LEGO Mindstorms) and all sorts of great stuff, or some people just use them as servers or even proper work computers if their stuff isn't too heavy for the machine.

And it's really cheap!

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Also there seem to be similar projects like Banana Pi (http://www.bananapi.org/) (is this one made by the same people as Raspberry Pi?) and related things like Arduino (https://www.arduino.cc/) which seems to be possible to connect to the Raspberry Pi?

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UPDATE: C.H.I.P. (http://www.getchip.com/) was suggested in this thread, which seems even cooler than the Pi now IMO!

So, some links from me to kick this off:

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"Top 5 Raspberry Pi based projects" (https://www.youtube.com/watch?v=plYeHEhhOaY)

A video showing off two kits for making robots, some weird camera with a bit too little information on it in this video, a gaming system and a media system.

Linking this mostly for the first project, since I was actually thinking about LEGO Mindstorms just the other day and then I found this, which is LEGO robotics using a Raspberry Pi (and if I understood it correctly it seems to work with the actual Mindstorms software or something..?).

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"Things you need to know" (https://www.youtube.com/watch?v=vw2nTpLFof8)

Useful introduction. A bit outdated and not about the most recent version, but still useful — just read the comments to find out about stuff that might have changed since then.

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"Raspberry Pi 2 workstation" (https://www.youtube.com/watch?v=XA95jzOyA9w)

A Linux guy trying out the capabilities of the Pi as a proper (Linux) workstation. He plugs it into dual monitors, overclocks it a bit and all sorts of stuff, and it actually ends up running quite well using a Linux distro. Of course, his work seems to mostly involve doing stuff in the Terminal, but nonetheless it's a graphical interface he's installed.

If you don't need the horsepower of the Pi2, i'd recommend getting a PiZero* Only costs $5 and is super-small, so it's ideal for embedding in a DIY project.

(http://i.imgur.com/tbVQUYa.jpg?1)

*They are sold-out ( again ) at the moment though.

Yeah, I know about those too. Seems a bit useless not to have even a single USB port tho, but maybe a hub that connects through micro USB could work? Do those exist or would I need an adapter? And no ethernet port, so I'd need to buy some USB Wi-Fi receiver as well if I wanted to connect it to the internet. That still adds immediate additional costs, tho.

Do you think a Zero would be enough for a LAMP server?

Seems worth it going midway and getting a B+ that has a cost in between Zero and 2 B just to get the USB ports and ethernet port built in. Seems to have more or less the same specs otherwise (one core, same GPU I think, same RAM).

You can use a micro-USB hub, but by doing that you lose the biggest strength of the Zero ( in my opinion ) .. its size.


Sounds like the Zero is not for you then ;)


For a LAMP server i'd probably go with a CHIP (http://www.getchip.com) instead ( if you can wait a couple of months ).

Right, micro, not mini.

CHIP looks really cool! Built-in Wi-Fi and that thing that makes it portable makes it seem extremely handy. And bluetooth! And it's even cheaper than the Pi! I could definitely see myself getting this.

I can't seem to find how many cores the processor has, tho? Do you know?

Seems the whole package I'd want/need (CHIP, PocketCHIP, CHIP case and USB charger) adds up to $67 already tho. :P But I guess I could start out without the portable kit since I never expected that from a Pi anyway and just get the CHIP and a case for $11 ($17.22 with shipping apparently)... Except I need to buy an HDMI ($15) or VGA ($10) adapter as well if I don't get the pocket thingy. That makes it $33.15 in total with shipping if I get the HDMI adapter. At least I already have cables.

Calling it a $9 computer seems slightly deceptive to me since it's not very useful for a lot of purposes without at least one add-on.

yeah it was the same deal with the originals. 35$ but then I had to get a wifi addon and I chose to buy a case and directly hook it up to a monitor rather than use a shell.

Regardless it's pretty damn cool. I've been toying with an idea to essentially crate a shock therapy device for condescension :D

No, Banana Pi is a knockoff.

I have a Raspberry Pi. I have it hooked up to my television so I can use Kodi on it to stream video.

I also have openVPN installed on there, which I use to access my home network from work.

Yeah, it's of course incredibly cheap either way. I hope people are using this sort of stuff in poor places to introduce computers in schools and whatnot. That'd be great use of this revolution.

Shock yourself into getting back to work when you're slacking off? ;)

It has a 1GHz ARMv7 ( Allwinner R8 ) .. which is based on the A13 (https://linux-sunxi.org/images/e/eb/A13_Datasheet.pdf).


For a LAMP server you don't need the HDMI / VGA board though .. nor a PocketCHIP ( obviously ) ;)


I understand were you're coming from, but most people already have a TV ( and a composite cable ) and a keyboard .. which is all that you need to use CHIP as a regular computer.

Yeah, I know, but that was just one of my ideas and one I'm unlikely to realise anyway because our net is too slow and we can't afford more right now anyway. So I would probably do something else if I actually got one.

Heh I wanted to make something that uses the google voice recognition to detect when someone starts a sentence with the word "actually" at which point a red light starts flashing and noise goes off.

PATENT PENDING! :eyebrows:

Don't forget to make it work with "I'm not a racist/homophobe/transphobe/etc, but..."!

That one would probably involve a taser of some sort.

I bought a raspberry pi last october and it's been sitting on my desk since then. I've thought about turning it into a capture device for recording videos, any thoughts?

Perf would be my only concern. I had some perf stuff when trying to do some emulator stuff.

I'm really interested to hear your results if you do try though. Having a cheap capture device would be great.

This is something I have investigate from sometimes ago when I realized you could produce a game a sell it for normal retail price directly with those kind of hardware. NO need for external machine, plug and play on your tv. They are call single board computer: https://en.wikipedia.org/wiki/Comparison_of_single-board_computers. The raspi and equivalent are roughly equivalent to a HD gamecube, but some board are more powerful.

The main interest as a game developer is that they also allow for full customizable controller per game and erasing the diference between video games and toys (going beyond the Toy to life trend like skylander or amiibo)

Unfortunately the Raspberry pi GPU is not compatible with unity.

BUT the odroid C1 and the CHIP ARE!! (gpu mali400)
http://www.hardkernel.com/main/products/prdt_info.php?g_code=G141578608433

For all your electronic extension need I recommend:
https://www.adafruit.com/
In learn there is many project to make you up to speed with various stuff (down to your VR helmet).

If you want to go hardcore there is also computer with FPGA ie customizable hardware CPU circuits ( https://en.wikipedia.org/wiki/Field-programmable_gate_array ), which can be VERY handy, but it's also more expensive, the accessible posterchild is teh Novena:
https://en.wikipedia.org/wiki/Novena_(computing_platform)
Although to start with FGPA harware programming this comes handy
https://www.adafruit.com/products/451
Apparently learning verilog (hardware programming language) is a bit hard as it is lower level that assembly (you literally rearrange the hardware circuit instead of addressing it with instruction) but initiative set out to democratize it:
https://blog.adafruit.com/2015/04/14/the-new-lucid-hardware-description-language-and-the-mojo-ide/

The gist with FGPA is that you are free from concept like "core", you can make the hardware execute sequentially or in parallel "at will", making as many non homogeneous thread if you want too, or making some part parallel or sequential whatever you want. However compile time might be longer.
https://blog.adafruit.com/2013/06/18/how-fpgas-work-and-why-youll-buy-one/


FGPA and raspi
https://blog.adafruit.com/2015/10/23/fpgas-for-the-raspberry-pi-piday-raspberrypi-raspberry_pi/

The raspi have a gpu that can encode/decode HD video at 30 image seconde on the fly I believe, this should not be a problem, people make camera with it using a camera captor. The problem would be to get the video signal. I haven't done this but there is many tut if you google it.

Nice, I'll try doing something with those tutorials. I imagine that all you need to do is change the input method, but I'll have to see how complex/simple that is.

Pairing a computer like the rasp with a massive resource hog like unity is a recipe for disaster. Similar to pairing unity with a gamecube.

Something lower level with the ability to directly manage data on the other hand is feasible. I really like the idea of a game so standalone it comes with the computer that runs it.

Plug and play games have been a thing for a long time though.

@infiniteSM

I didn't mean using unity ON rasp pi, but building unity game TO raspi.

I have used unity on netbook with power roughly similar to raspi when I was making the sonic clone attempt. Work just fine.

Although I heard godot might compile to raspi.

What do you mean? the fischer price mock console?

https://www.youtube.com/watch?v=jHepjitYJmM&ab_channel=JonTronShow

Yeah I was talking about indie bedroom coder level of being apple to do it. Ie you and me.

Oh.

Yeah, indie plug and play is pretty much non existent. Until now. :^)

That's also what I meant. Outside of the simplest games I don't see it happening. Unity runtime applications are crazy resource hogs for what they are.   

Well it run already on those target, I play them on my tablet which is lower that that in spec. That's what made unity famous, mobile game, it has mobile specs.

My expensive tablet struggles like crazy to run hearthstone but runs other non-unity games with far nicer graphics much better.

Too bad this game is poorly optimized, using unity don't prevent you from doing that. Like I said I play unity game with unity splash screen and all and they are fine. I'm using a no name tablet brand with 800gHz 1 core, 512mo of ram, android 4.0.4? IT's FINE! And I'm playing 3D games!

I do have plenty plenty other game not compatible for it though.

My computer was 4gb intel with gma950

If the game is simple enough then even a bloated resource hog of an engine like Unity will still be fine. I'm comparing it to other engines or native code though. It seems the rate it loses performance and uses resources compared to graphic complexity is asymptotic.

What does the unity splash screen have to do with it though?

it proves that it is unity and that the devs didn't care about removing it.

Ah ok. I thought there was something else I was missing there.


On that note I googled around looking for examples of people getting unity running on a pi and couldnt find much. Timmy maybe just give it a shot and post back your results. If the game is simple enough then maybe you will be fine. I'd be interested to see how it performs relative to an Android tablet with similar specs.

Because it was made with free unity, ie more likely to be made by people with less skills.

Did I said gamecube quality?

Though you are dissing an engine who took off precisely because it outperform other on mobile.

Which other engine? Unreal? it's only lately they are really catching up. Most other are 2D engines and native, congratz, you are the realest dev on earth.

Isn't portability the reason for unity taking off, and not performance?

Performance is not at all why unity blew up. Ease of use for developers and platform support were the biggest reasons.

No need to insult me because I disagree with you Timmy. Please don't be childish.



Posted while I was replying. Yes I agree. Portability and developer friendliness.

^

Wait when did I insulting you WHAT?

I said "don't diss" is that an insult?

But no I'm really adamant on what I said for exactly experimenting that way, it run fine. saying otherwise is factually not accurate.

I think he meant the sarcastic-sounding "congratz" thing.

I've found an interesting project with stuff I already have (except for an adapter I ordered yesterday).

OUYA! Does anybody remember it? The flopped little miniconsole. I actually have one.

And yesterday I found out my old monitors I'd thought to be dead for years now actually suddenly work again, so gf got an extra monitor for her PC and I have one I can play around with now — only catch is it's fairly old and only has DVI and VGA and the OUYA only has HDMI output, so I had to order an adapter from HDMI to DVI and audio (gf has a portable Bose speaker I can plug the audio into since the monitor doesn't have any speakers).

So while the console is kind of useless out of the box and the controller isn't that good, being an Android device it easily plays with other controllers as well, such as my bluetooth PS3 controller. So I thought about turning it into some emulator hub for old games. Maybe I could get some cool USB versions of NES, SNES and N64 controllers in the future as well. Watched a review recently and they seem to feel genuine enough.

I also found out you can even run Debian on this box. And lots of other stuff.

So I'm going to keep reading and mess around with this little box and I might actually have found some use for it after all. And my desire for a minicomputer is somewhat satisfied. :)

You may already be aware but if you decide to go the emulator route there's a cool project which works on a lot of os'es and smaller devices. 

Retroarch which is based on libretro. http://www.libretro.com/

They have an android app here too. https://play.google.com/store/apps/details?id=com.retroarch&hl=en

There is also a image you can use to boot into a nice preloaded set of emulators for raspberry pi called retropie http://blog.petrockblock.com/retropie/

The comments on the Android app seem incredibly negative tho. :( Seems it used to be good but has gotten messed up recently or something.

cool :)

The android one I admit I've never tried. I've only tried the rasp pi one. It works quite well overall.

I saw some YT video of a couple of emulators running on Ouya (in the default OS) and it looked like it was working well, so I guess I'll try and do what was done there.

https://www.youtube.com/watch?v=DfPyPQ_Gmyw

Oh wow I didn't realize so much stuff is already essentially built into the ouya. Awesome

Got the adapter and it's working. Sort of. The audio cable didn't really work at all, but it wasn't a problem since our speaker supports bluetooth anyway and the Ouya paired with it successfully.

But the resolution. Apparently the Ouya is really picky and since the monitor doesn't match up with 1080 or 720 perfectly, it actually defaults all the way down to 640x480 even tho the monitor supports 1680x1050.

There are no menu options to force a resolution, but I found this: http://qandasys.info/changing-forcing-screen-resolution-on-ouya/

But I don't get it. What does it mean? Does the Ouya have a terminal I can type into, or how am I supposed to input this stuff?

EDIT:
OK, bluetooth speaker lags too much actually. How am I supposed to use the adapter? Both the HDMI side and the DVI side have audio cables (the headphone/speaker kind you put into computers) but of course there is no such opening on the Ouya since HDMI already transfers audio. But just plugging the one on the DVI side into the speaker doesn't work, so what do I do?

EDIT 2:
I think I rooted it but I don't want to download Xposed and Mod Collection from all these shady websites where people have put them. Even if I trust the uploaders, I don't trust the sites... Someone had it on their dropbox but the links are dead now. :(

EDIT 3:
Partial success, at least! Didn't have to install anything additional to find an N64 emulator on the regular Ouya store (tho it seems to be the only one that appears when I search for 'emulator').

(http://i.imgur.com/6AytZ0T.png)

The low resolution problem ceases to be a problem with old games like this, of course, but I wish it would cover the entire screen... And the audio problem still isn't fixed. Lags behind a lot on bluetooth so I need to get the cable working somehow...

I actually just put the finishing touches on a Christmas present project that I made using this approach. Retropie is a relatively easy way to build a capable emulation box using a standard Raspberry Pi. It streamlines a huge amount of the setup, and gets everything installed with very little fuss. Definitely a good idea for beginners who might not have as much experience dealing with Linux.

I'll post some pictures of what I threw together sometime in the next two days. (before I wrap up the present) It's a pretty good idea of some of the more entertaining aspects of using one of these micro-computers.

I've really been psyched about using one of these things to create a custom arcade cabinet. And not just a MAME box, I'm thinking of brand-new custom-designed software. Sadly, the Raspberry Pi that I had previously was a model B+, and not the new Pi 2. So I wasn't able to test Unity's performance on it. From what I understand the Universal App build for the Pi 2 using Unity is quite lacking in performance. This is not surprising, given the nature of the engine, and the specs of the Pi 2.

At the moment, one of the more promising engines for Raspberry Pi game development is actually Godot. While it doesn't yet have official support, I know that a few of the Godot users have managed to successfully compile and run both the engine and the editor for the Raspberry Pi. Aside from that there aren't that many options for full-featured Raspberry Pi game engines.

I'm a bit confused about this talk about running a program on or compiling a program for the Pi. I thought you had to install some established OS like a Linux distro anyway? Or does the Pi have something preïnstalled, or something specific that can be installed, when it's new?

It depends on what Pi you are using. The original run of the Pi mainly focused on using Raspbian, a Raspberry Pi-optimized version of Debian Linux. This was the most common OS to run on it, though you were free to install any other OS that you could get running on it. Several different versions of Linux were ported to the original-model Pi, so you have options.

The Raspberry Pi 2 is the second major hardware iteration for the platform. It bumps up the computational power and efficiency a little bit, but still costs the same as the original Pi. In keeping with the point of the Raspberry Pi project, the Raspberry Pi 2 is more of a refinement, and not an attempt to jump into the hardware arms race.

Most of the Linux distros that were compatible with the original Pi have already been ported to the Pi 2. One major change though, is that Microsoft started officially supporting the Raspberry Pi 2 with Windows 10. There is a minimalistic version of Windows 10 that has been optimized to run on the Raspberry Pi 2. If you have a Pi 2, you can download it from Microsoft and try it out. And the new "Universal App" system that Microsoft introduced with Windows 10 is compatible with the version of Windows that runs on the Raspberry Pi 2. So if you have that version of Windows 10 installed on your Pi 2, you can get Universal Apps running on it.

Unity introduced Universal App support with one of the 5.x version upgrades. Thanks to that support, it is now possible to get Unity builds running on a Raspberry Pi 2. (but not previous models, only the Pi 2 is compatible with the stripped-down version of Windows 10) From what I understand, the performance is not very good, though. I haven't done any testing myself, as I only had a Pi B+. I might get around to trying it out later this year, but I'm not in a hurry. I have other projects I want to focus on first.

Just to clarify, the Universal App builds are what will run on the Raspberry Pi 2. The Unity IDE does not currently work on the Raspberry Pi 2. So you can port projects to the Pi 2, but you cannot create or edit Unity projects on the Pi 2.

I worked on a Pi 2 using the Windows IoT build this summer, but it turned out to not be what I needed. The version I tinkered with had no OS, it was just a loader that recognized and ran universal applications sent to it. It required Visual Studio to send, which was annoying. The real dealbreaker was that there wasn't even an audio driver yet, though. I didn't set up the Pi so I don't know if there is an actual Windows 10 OS or just what I dealt with. I sure hope so, though.

I'd never heard of this universal app madness before. I would have never dreamed the first running version of unity on a pi would be through windows haha


RKain are you using the pet rock image or did you build up your own?

I'm using the Pet Rock SD card image. You don't have to go that route if you don't want to. Pet Rock also releases an installation script that you can run on top of a different Linux distro if you want to. It will install all of the same software and get things set up for you, but won't come pre-bundled with an OS.

I had no specific OS needs for my build, so I just stuck with the default Pet Rock Retropie SD card image. It was quite easy to get it up and running. The most complicated part was getting the controller set up, and customizing performance for individual games. I was focused on the SNES, and some of those games perform differently based on what emulator you're running.

The default Pet Rock SD card image is set up so that it runs Raspbian OS, but doesn't fire up the X GUI. It boots the OS, and then immediately runs Emulation Station instead, and lets that serve as the graphical front-end. This allows all of the emulators to run with a greater degree of system resources, and perform better. I haven't had any complaints so far on the general structure of Retropie. It's a fantastic way to put together a quick, cheap retro-box.

That's the one I used too. The packaged front end I was having issues with at the time but I suspect that's a usage error on my part. It worked pretty good overall. I think it was something like certain emulators werent displaying rom lists.

I will have to take another look at it during my vacation.

If you're not afraid of editing some text files, it is actually possible to customize the rom list displays pretty handily. I did that with the Capcom CPS section. Those packages are multi-part, and are generally a pain in the butt for displaying in a list. But if you know what you're doing, you can re-name the files, scrape the metadata and images for the files, revert the file names to their original settings, and then disable emulation station's search function for that platform. Once you've done this, emulation station will use the XML file generated by the metadata scrape for the rom list, and ignore any detected files. You can even do this with your own custom XML file if you have custom art you want to use, or custom descriptions.

Pretty much everything in emulation station can be customized to one degree or another. I'm really loving that front-end.

I am currently writing a multi-threading operating system for an 8-bit atmel chip (20 Mhz). The Pi is way too powerful:P

I'm digging this one out of the backlog for a necro-post. Partially because there's something new I have to add to the discussion. Partially because I think the discussion is worth continuing.

There's a new micro-computer coming out at the end of July, called the Rock64. It looks fairly promising, and it's going to have a decent number of OS options available at launch. One of its strong selling points is that it will have different price tiers, based on what level of RAM you want in it. The standard 1GB model is going to be cheaper than the current Raspberry Pi, coming in at just $25. Tack on $10 for the 2GB model, and another $10 on that for the 4GB model. Quite reasonable, with some solid performance. As with most new tech, you'll probably want to read some reviews before placing any orders.

But more potentially significant, it is now possible to compile and launch Unity applications on the Raspberry Pi. It was "kind-of" possible to do this using Universal Windows Apps using an installation of Windows IOT. However, this was highly experimental, and not particularly well supported, by Microsoft or Unity.

In the past few months, Android TV has been successfully ported to the Raspberry Pi, and GPU support has been added to increase performance. On Monday, I was able to install Android TV on my Raspberry Pi 3, and sideload a compiled Unity Android APK. This is just a very small prototype, but it established that it is now possible to get a Unity application running natively on a Raspberry Pi with GPU support. I was even able to test out basic shadow-casting, which worked just fine. My dreams of assembling a miniature arcade machine with my own custom games on it are drawing closer.

Wow, this thread is that old?

Cool news! I still haven't found any valid reason to actually get any kind of smol compyootar nor felt like I've had the money to spare for something so unessential to my needs, so still no experience. But if a project comes along in the future that naturally lends itself to using one, I'll be on it!

It's understandable, not everyone's project needs or is appropriate for such a device. But I've always been interested in some more hobbyist ideas that would work well with minimal specs. The big plus of using a mini-computer is three-fold. Size, cost, and access.

Size is obvious. These things are insanely small. I'm not kidding, SO small. You can squeeze them inside just about anything. They also run silent and run relatively cool. There's a reason why they're so popular with hobbyists and DIY-ers.

The cost advantage is more relative, but it's not insignificant. If you are looking to get your hands on some computing power in a tiny form-factor, micro-computers are a great way to get everything you need for a very reasonable price. The current going rate is in the sub-$40 range. The most popular of the lot, the Raspberry Pi 3, can usually be had for around $35, brand-new. And while previous versions of the RPi would often need add-ons through USB, the current RPi3 has wifi and Bluetooth built-in, right on the board. So that $35 gets you pretty much everything you need.

Access is more for the low-level coders and hobbyists, but it's still worth considering. All of the popular micro-computers essentially give you assembly-level access to everything on them. If you want to dig right down to the metal and make your micro-computer do some low-level stuff, you can do that. Most of them have an array of GPIO pins as well, which can give you all kinds of crazy features. You can wire in your own custom buttons, or even output power from these things. On one project I used them to add LED-lit buttons, and activated and de-activated the LEDs for the buttons through code.

One of the biggest drawbacks to these things is a noticeable lack of game engine support. Almost none of the major middleware companies has released targets for the RPi and its various competitors. The lack of one standard or OS to target is almost certainly part of this. But it has still held back game development on these things. Not everyone feels comfortable enough with low-level coding to dig into custom engine programming. Having the possibility of targeting Unity projects at one of these devices is a pretty big development.

Wow thanks for the news, any link to verify that? I just recently look for the gpu support and find nothing tangible! Does it works for old raspi too? I mean the 5$ version!! The thing is that it makes possible to sell "hardwareless" game directly and have custom controller. So far the controller (i mean good) is the most complex things to do, I wanted wii type of tracking and pointing, but tracking isn't mature yet.

Here's a quick link. (https://www.youtube.com/watch?v=WMOCMX3pZwM&feature=youtu.be)

In the video, it shows a game running with 3D graphics in its menu. I did notice that there were rendering artefacts when displaying the skybox for the game. This was actually something I noticed in the project that I exported from Unity. When you could see the default Unity "world" graphics, it would display those same rendering artefacts. When I put a plane in front of that area, it solved the issue. So if you wanted to put a 3D Unity game on there, you would probably want to roll your own skybox solution, and not rely on the built-in horizon view in Unity.

Oh, yes, don't get me wrong; the prices are very reasonable—it's just not reasonable for me to get one at all right now. :P

I'm guessing it's a hardware issue, since it should work if using an OS that Unity already supports like a Linux distro? They don't have a graphics card, right? Is that the problem?

They don't have dedicated graphics cards, but they do usually have GPUs. (depending on the model) The standard form factor for these usually does come with its own GPU. The OS is actually the issue. Unity has a Linux distro target, but that target only works for x86 architecture. All of these microcomputers use ARM processors. So you would need Unity support for an OS that is targeting ARM architecture. Basically, that boils down to Android. And up until recently, there had not been that many efforts to port Android to the Raspberry Pi.

The reason is actually kind of obvious. The Raspberry Pi has no touchscreen, by default. You can plug it into a touchscreen. But the core hardware is not designed to run a mobile-phone OS by itself. This is why the usual OS installed on the Raspberry Pi is a Linux ARM distro called Raspbian.

The advent of Android TV convinced more developers to start looking at getting Android onto the Raspberry Pi. Android TV is optimized for interfaces that don't rely on touchscreen controls. That's why there is now a port of Android TV running on the Raspberry Pi, and why I am now able to get Unity projects running on the hardware.

Speaking of alternative of Rpi, there is the odroid series, that is compatible with unity, but they had no 5$ model as of late (need to check back, okay cheapest still at 28$), also have more standard mobile GPU (amli series), which are supported.
http://www.hardkernel.com/main/products/prdt_info.php?g_code=G145326484280

If you have other alternative that are cheaper and more standard gpu I'm listening!

Yes, the cheapest of the main ODroid series is around the same price as a standard Raspberry Pi 3. But they do have better out-of-the-box Android compatibility, which would make them much better for running native Unity Android apps. Also, they provide multiple different power options. Oddly, the $46 model they have seems to have better performance and more advanced OS support than their $59 model. I think it comes from the improved data transfer options that the $59 model sports. It's their only model to have USB 3.0 ports.

The point is, if you are looking for some nice, cheap options for lower-end development and deployment, the opportunities are now there. These micro-computers are more of a viable option than ever before. And a nice healthy, competitive scene provides smaller indie devs with better hardware at lower prices.

I was just poking around, and I saw that the Orange Pi One and the Orange Pi Plus2 both support Android as well, and both have GPUs that would make them viable options. The Pi One is a little lean when it comes to RAM, so that's a limiting factor. But it's also one of the cheapest micro-computers I've seen, coming in at just around $20. Quite feature-rich for such a low price, and definitely a potential option for games that don't need a lot of power.

The Orange Pi Plus2 is a bit more expensive than the standard Raspberry Pi. It comes in around $50. But the feature set for the Plus2 is huge, with twice the RAM of the standard micro-computer, and lots of other extras. (built-in wifi with an actual antenna, analog video and audio out, built-in microphone, a SATA port for hooking up hard drives, and many more) If you don't mind spending a little extra, this thing has a ton that you can do with it, and more power to play with than usually comes standard on these micro-computers.

I was able to do a little testing last night, and I confirmed that a basic empty scene with a few basic 2D GUI elements will run at 60 fps at 720p. I'm having a little trouble getting my Raspberry Pi to output proper 1080p. I'm not sure if it's an issue with the Pi setup, or with the settings for the Android install.

Next up is testing joystick support, and getting some interactive/animated elements.