I tried the app and I did notice the first screen is "Select Storage Location" after you try to add a new backup and it lists: local dir, aws, gc, azure, b2, s3, sftp.
So I indeed guess it can as well be used as restic frontend (but I am not really sure to what extent it uses restic and whether blobbackup is just a gui/skin for restic)
I think you may have tried our original app (the original folder in the github repo). I need to clean up the Releases page. That version used a custom backup engine and allowed backups to a number of storage providers (S3, B2, SFTP, etc).
The new app uses restic as the backup engine and only supports backups to B2 right now. Sorry for the confusion.
So I indeed guess it can as well be used as restic frontend (but I am not really sure to what extent it uses restic and whether blobbackup is just a gui/skin for restic)