The Install Process, Step by Step
Grab the APK from the official Download page — never a third-party link. Before opening it, flip on installation from unknown sources in your Android settings, since this app ships outside the Play Store. Once it's installed, open it and sign in with your existing account, or register fresh if you're new.
To stay updated, just re-download the APK from the official page whenever a new version shows up on the Announcements page.
When the Install Doesn't Go As Planned
Almost every installation hiccup traces back to one of two things: unknown sources not enabled for whichever app opened the file, or a half-installed older version conflicting with the new one. Uninstalling anything old before installing fresh usually fixes it.
If the app installs fine but login fails, check that you're using the same registered number as your other devices — installing and logging in are two separate steps, and finishing one doesn't mean the other's done.