A complex subject to handle while writing a game is the Android screen size fragmentation. Low-end phones have resolutions of a few hundred pixels, whereas some high-end devices provide resolutions of more than two thousand.
There exist several ways to handle various screen sizes. We can adapt graphic resources, use black bands around the screen, or apply and adapt responsive designs to games.
Another simple solution consists of rendering the game scene off-screen with a fixed size. The off-screen framebuffer is then copied onto the screen and scaled to an appropriate size. This one size fits all technique does not provide the best quality and might be a bit slow on low-end devices (especially if they have a lower resolution than the off-screen framebuffer). However, it is quite simple to apply.