Hello. I'm not an expert in developing smartphone software, but I ever tried to code some very simple apps and it's really running on my Android phone. I was very excited
Unfortunate, it's still considered hard to develop software on Android at the moment. The hardest part is the compilation process to produce (Android's executable) APK files. We have to install and configure lots of things like Android SDK, NDK, Java properly. Actually, it's not hard but because the available information is not detailed enough for most programmers to understand.
Also, lot's of the visual components aren't able to run on Android, we only have some very limited components to use for the User Interface.
Good news is, now several volunteers are working hard to make FCP/Lazarus easier to produce Android's software.
Although now the result is still far from good, but I think it's the time you should try to learn develop Android's software. When FPC/Lazarus is good enough, you will be ready to develop apps to run on Android.
And Yes, you can develop Android's apps on your regular Windows and Linux computer. I'm using Linux.