For Android devices that cannot use Google Play — Huawei phones without Google services, for example. On every other device, install Klubraum from Google Play instead.
From Google Play, Klubraum keeps itself up to date. A direct download does not.
Open Google PlayAn app installed this way never updates on its own. Klubraum tells you when a new version is out — come back to this page and install it over the old one. Your data stays.