Blöckle Boulderhalle Ravensburg
The Boulderhalle in Ravensburg is a climbing hall fully focused on bouldering. They have some great boulders for starters, so check them out.
The Kletterbox in Ravensburg is the largest climbing hall in Oberschwaben. They focus on climbing with a rope, so there boulder area isn't too big.
The DAV Kletterzentrum in Friedrichshafen is the public climbing hall in the area. In the morning it is occupied by schools but they have public opening hours in the evening.