I toyed around with a dev phone a few months back, and in general I found that the Firefox OS environment has a lot of drawbacks that can be tough to push through as a modern developer. You're working on a platform that targets low-end hardware, is limited to browser-based technology, and lacks the community-generated frameworks that exist on iOS and Android.<p>I found it took too long to get anything done when compared to other platforms, and overall was just a mind-numbing experience.<p>I don't know that Firefox OS will ever catch up to the other devices in the US as far as developer tools and community go, but I'd certainly take another look at it if it did. Right now, I don't have the kind of time to burn on free projects that I did a couple of decades ago.