How to contact the developer of Locker app (Locker
See here: https://gitlab.com/fdroid/fdroiddata/commit/3d3bd72c4b3abb9349a4876ec52d9faea3e6d657
The developer and upstream repo seem to have disappeared. Only thing to do is someone downloads the source code archive from the f-droid website and starts maintaining the app again.
Means? the maintainer /dev is gone or dead