Hello!
Thank you for your interest in Polycode! Answers below, but to clear up something you mentioned: there is currently no development happening on mobile ports of Polycode, though it WILL be a major focus in the coming months.
1 and 2.
Polycode has been my main personal project for nearly 6 years now and I use it for almost all commercial and personal projects that I work on. I made it open to the public because I think it can be a great resource for other developers and their input will in turn benefit (and has already benefited) the project itself. I work on it almost fulltime at times, but I do not want it to become my job, which is part of the reason why I released it under a liberal open source license and have been ambivalent about accepting any kind of money (even donated money binds you with a responsibility that I am currently not looking for). I want to be able to walk away from Polycode development for any length of time that I need for other projects and not be restricted by financial or other obligations. That said, I am planning on continuing working on Polycode indefinitely and it will most likely stay my main project. I've already put 6 years into and it will remain my own framework of choice, so I have no intention from walking away from it.
I won't go into how Polycode is different from X or Y framework. If you look at the feature set and the code tutorials, you can get a pretty good idea on your own.
3 and 4.
I am currently the single maintainer of the repo and I accept pull requests almost on a daily basis and there is usually an active discussion happening between the people who are most closely involved with contributing to Polycode on Github, the forum and IRC. Most of the feature enhancement pull requests that result from these conversations are accepted after a quick code review on my end and of course all and any bugfixes contributed by the community. Feature enhancement pull requests that are sent in without prior conversation and don't immediately make sense I tend to ignore, since every pull request involves my looking through the diffs, pull it in and testing it and right now there are still a lot of bugs that I want to focus on.
There are about 3 people right now that are actively contributing to Polycode's development. Ultimately, I am the final gatekeeper of what features go into the project and I want to keep it that way, at least for now. I am, however, always open to suggestions and always welcome a discussion about the merit of doing things this or that way. So far it has worked out well. Polycode's license allows you to always go off and do your own thing with it (and others have; one of the main contributors to Polycode maintains her own branch that's tailored to her own needs and syncs it with Polycode's main code base once in awhile).
5. Yes, the IDE has a networked debugger that the player connects to and will give you a backtrace in case of a crash, though currently there is no support for breakpoints (also planned in the future). It also allows you to execute code in the running player from the IDE console.
I hope I answered your questions!
- Ivan