If you want to land the stage 1 make sure the fuel at 50% and stage 2 is really dont use too many fuel you can go to the moon with stage 2 sadly you cant land with stage 2 because it only have 1landing leg
You download the link first you need to do find Falcon 9 the find this zip then press the tree dots "..." and then Decompress the file do like i do find the decompress file open it the long press the file copy the file go to android open it go to data open it find com.stefomorojna.spaceflight...