Can I ask a question about a non-Apple app that is used on iTouch, iPhone, or iPad on Ask Different? I know it's a forum about Apple stuff, but I am using the app on an iTouch. I'm talking about an app like SoundHound, Splashtop, etc. You know, something not made by Apple but used on an Apple product. If I can't, is there a more appropriate Stack Exchange site to ask on? Thanks.
Yes. See https://apple.stackexchange.com/help/on-topic for a list of topics you can ask about; third-party software that runs on Apple devices is explicitly included.