You have limited downloads before signing up.
You will have to have an SD card imager program, free on web look around.
You will need to delete all 4 partitions on the existing SD cards, then quick format them before imaging them.
You will consume several hours learning all about imaging, ripping copter apart, controller apart, and losing the screws, etc..
You may get stuck in Preflight Update. These two downloads have a password other than sololink in the wifi connection.
Therefor you wont' be able to wifi connect your app right away.
You will have to do the factory reset after installing the SD cards steering you into the Preflight Update brick wall.
Don't bother, just buy Solex and use it to install Open Solo 4 and you will be smilin' while your flyin'.
Loading Solex and Open Solo 4 is a much better use of your time because it is current, has a future, runs on current Android.