I'm not an Android specialist, but I have written few small Android apps. If you want to write Android apps, well just start doing it. First 100 apps you write will be shitty, but then maybe you'll find your way. Books, courses, bootcamps would help, but you need to write - every day. And actually do nothing more. I cannot advance in Android development because I realised I already do to much of web development and business stuff. For coding you need to find your 'zone' a time and place where nothing distracts you and you just follow your idea. Of course you need tools like programming knowledge first. Such process takes years, it's like playing on an instrument. It's for everybody, but you need to give all the time you can .
Coding app by yourself is the only solution when you don't know what do you want to build, because you can try. If you hire a coder he want's to know what to do, he cannot read your mind .Only you can read your mind. So if you don't have time and you want the app first think, then hire a programmer to build you a prototype and be prepared to put to trash the ideas, and this is going to cost you a lot .

If you're serious about the app and you don't know how to start take a pencil and piece of paper and draw pictures how to you see it working . Don't worry about tech stuff. Start with design, not the other way around.

It’s okay if you don’t know anything about app development (that’s why you’re hiring an expert), but you should know a lot about what you want from your developer. Start by identifying your main objectives for the app, your timeline, and your budget. Then I’d recommend tapping into your professional network – who do you know with a great Android app, and did they have a strong software engineering background? Ask them who they hired or what services they used to navigate the process or
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