Apps don't make money. You're better off making your own cryptocurrency/blockchain which is something I'm making and hoping to finish in 5 years for a very niche area. But if you don't have capital to start you off ... the quickest way to making a million these days is through social media. I suggest finding a very unique cat and posting it in different settings in Kenya, like the Masai Mara, Kibera slums, Obama's hometown Siaya. Ensure you hashtag effectively.