SMS Backup+ is outdated
The version in fdroid is 1.4.8 while the version upstream us 1.5.5. There is an important fix in git (1.5.6) for KitKat and higher so a beta build is also needed.
The version in fdroid is 1.4.8 while the version upstream us 1.5.5. There is an important fix in git (1.5.6) for KitKat and higher so a beta build is also needed.