The main guides on this site each cover one task: signing in, registering, installing, redeeming a code, reaching support. The articles here go after narrower questions that come up once you are already using the platform, and each one points back to the guide it builds on.
Same rules as everywhere else on the site: nothing is invented, every figure comes from what the platform itself publishes, and where something is not published we say so instead of guessing. You will not find gift codes, support phone numbers, APK files or version numbers here, because none of them can be verified from outside the app.
A topic earns an article when people clearly ask it and none of the main guides answers it properly. If you are just starting out, the login and registration guides are the better first stop; come back here when a specific problem turns up.