KeePassX

On Linux, the database is saved by default in /home/user/foobar.kdb
That's wrong. User settings and application data should never be dumped
into home. The db should be saved instead by default in
/home/user/.keypassx/foobar.kdb

On Windows, it's saved in the same folder with the .exe
That's wrong too. If multiple users use this application on the same host,
there will be confusion regarding the database files. Sure, the dbs are
password-protected, but it's ugly to just dump everything in the same
place.
It should be saved in %AppData%\keypassx\foobar.kdb