I code four new apps for Android (three games and one business community app). I want to invite testers and get feedback from users. Can I do that here, or do you know where I can invite users to test my apps?
This site is about solving issues users have with their Android devices – not about seeking staff for develpoment, testing etc. So: No, you can't use this site to invite testers.
As for where to do that: I'm not aware of any SE site permitting that. Some forum might be a good place; see Where can I ask questions that aren't Android Enthusiast questions?