I'm creating a small messenger and I wanted to know if it makes sense to store user passwords double-hashed in our backend-database. I wanted the user the register in an app, which should save a hash of the password and login with this hash in our system, which should not save this (1st) hash, but should somehow hash it again.
This would prevent someone who somehow got a (doubled) hashed password from our database from logging in into our api (since he needs to provide the 1st hash) and also would allow the app to not store the passwords of the user in plain text.
Is this a good idea? Should I just stay with the first hash and not hash the password again when using it in our backend-db? I read that something like this might be insecure as hashes become less secure the more often you hash them again. Should I maybe use different hash-algorithms for both actions? Which algorithms should I use?