Where can I find free android and or iPhone app scripts?

I'm currently working on a few app ideas and can appreciate not starting from scratch. If any of you guys know sites that have reverse engineered or clone like android/iPhone scripts that would be great. I know there are sites charging thousands for this but I'm sure there has to be someone giving them away.

Look for open source apps in GitHub. Read the license whether it allows commercial use or directly contact the person.

Thank you!