My primary language is C++ too, although I hadn't heard of Marmalade before. I had a good dig around their website but I'm curious what your impression was using it in a project - would you use it again?
This is my 2nd project with Marmalade, the first was
Little AcornsI use Marmalade just as a platform abstraction layer. It keeps me away from XCode and ObjC, but I write my code mostly-from-scratch in C++ and GL ES. Marmalade handles platform-specific bits such as initialization, input, audio, suspend/resume, and so on.
It generally works well - and being able to build+deploy from a Windows machine is, for me, a huge advantage (as I've been using Visual Studio for maybe 15 years or so)
I'm likely to carry on with it, but it's had a few problems that keep making me reconsider. The big one at the moment is iPhone 5 support - you can't submit iPhone 5 (1136x640) apps without using Apple's latest SDK, but we've got to wait for Marmalade to update to that and release a new version. That's taking a while (longer than Unity and Flash/AIR, which have to do the same thing)
But there's also been times that bugs have gone unfixed for quite long periods, and there's very little support on the forums (and the Marmalade forum software is terrible, no 'edit post' or way to subscribe to threads).
There's been signs that things are improving in that area - they held a free Developer Day at their offices a couple of months back, which was very useful, and they've talked about replacing the forums. But they do seem to be a fairly small team working on an increasingly large and complex product.
For me, still seems better than the alternative (dealing with XCode/ObjC, and Java/NDK on Android), and keeps almost all my development work on a single platform. But it's very frustrating at times when you're just waiting for a bugfix or support for the latest iDevice, and you can't do anything to speed up the process.