As I've looked through the forums I've seen many people asking about ads in app inventor apps. I myself have experimented with App Inventor and believe it's a valuable tool for begginers in app development. Anyway, I think I may have found a way to incorporate ads into apps made with app inventor, altought it would not be for the faint at heart. My theory is using tools such as APKTOOL to decompile the app (and if apks work the same as other software, this would give you the source code) You could edit this code, as well as upload t into an adSDK such as Adsense maybe? I would like to start up a discussion on this, and maybe even test it once skewl is over.