Use the guides provided in the help documentation. Although they are not easy to follow, as many including myself will attest to. I managed to get the player compiled for android but my game would not. It doesn't help that the guide uses an older ndk than is available from the link provided. I am really quite disappointed with AGK's guides about this, as it is a main selling point for AGK. I don't see anything in the sales blurb telling you how hard it is to actually compile a game for said devices, just how EASY it is. It is misleading in reality, as it gives people the impression the whole process is a simple as one click. Once you have it, you realize that is just for testing purposes and not how you make a standalone for the device.
I have been hoping for a revised guide, or even better a video to take you through it. I spent a week going round in circles trying to get a test prog onto android, and as I said the best I could manage was a compile of the player
Good luck, read the guides and check out threads here as lots of people have struggled with this.