VVM support

A community member, kop316, has made great progress on VVM support. He made two apps, vvmd to support backend downloaded voicemails if your carrier, and a front end GUI, vvmplayer to display them. Both packages are in Debian Testing

On installing vvmd, you need to restart your phone or start vvmd with

systemctl --user start vvmd

Uou can also check the status of vvmd with:

systemctl --user status vvmd

A database of settings can be found here, and you can enter them in vvmplayer: https://gitlab.com/kop316/vvmd/-/wikis/Carrier-Database

Unfortunately, porting this to different carriers does not seem to be as simple as MMS, so if you want to help port it to new carriers (and test ones), please join us at:

#opensourcemms:matrix.org (Matrix) or #opensourcemms on OFTC IRC