Hi Hive account@smade.
I would suggest javascript for frontend web development (and it can be used on the backend too - ie nodeJs) or Java to develop Android apps. The latter might be more difficult. You can build hybrid apps with javascript too though.
Good luck with your learning.

PS. I resteemed your post for free. I notice that many of your posts receive no payout. I'd suggest to start to use free resteemers (like me) on the #resteem channel in order to get some visibility :D
( Click the tag above or https://steemit.com/created/resteem )

All the best