You ask: "Is it very hard to do that" which is a bit ambiguous as a question. But here are some tips for starters: - Pick a niche for your app that is very ne

You ask: "Is it very hard to do that" which is a bit ambiguous as a question. But here are some tips for starters: - Pick a niche for your app that is very nerdy, don't do something mainstream, that would make too mayn people interested in your offering. - Do not have a website or a youtube channel that helps people use your app. obscurity is absolutely crucial for your Android apps business success. - Please pick a very cheap price with a crummy number like, say, $4,97 to evaporate your margins. - Understand that consumers hate pretty icons and nicely animated user interfaces. Your app has to look like a Linux desktop of a guy, who feels most comfortable to be in terminal all day. - Please make the billing process a PITA, otherwise things would be too easy! Better yet, make sure I can't even buy your app in most countries! - Don't invest in graphics! Make the app icon ugly und undiscernable! - Likewise, don't think about marketing. It is important that you just upload the app and let the app store do it's magic! It works 100%! - Make sure you have no customer support. If you have good customer support, that could build trust and drive sales, something we do not want if we want to be successful. - Lastly, let's make sure you disrespect quality programmers. Buy cheap code from a third world country! The delivered software architecture that breaks with every OS update and additional bag of bugs will be a constant maintenance nightmare. And after all, we want to have dreams, right? - Oh, and don't make the app useful. Make it a gimmick that nobody really needs! Keep the above in mind and surely, becoming a millionaire garage style with programming Android apps will be a peace of cake!