What is the ruling on explaining Android phone applications and inviting users to them while they contain ads? And what is the ruling on directing to useful websites that contain Google AdSense ads which cannot be controlled? And is earning money from download sites and link shortening impermissible if they profit from AdSense ads?

If the applications are permissible, then explaining them and advocating for them is not forbidden. As for advertisements that mix the permissible with other things, there is no harm in them, because they are not intended for their own sake, and what is overlooked in them is not overlooked in what is originally intended. The questioner should advise users and warn them against offensive advertisements.