Using adb, create a backup of the app using the following command:
adb backup -f freeotp-backup.ab -apk org.fedorahosted.freeotp
Using adb, create a backup of the app using the following command:
adb backup -f freeotp-backup.ab -apk org.fedorahosted.freeotp
I tested the setup on Debian Stretch (naive installation) and Jessie (LinuxGSM installation). The setup should work on Debian 8 (Jessie), Debian 9 (Stretch) and Ubuntu (16.04). However, If you're running on Windows or other non-debian based Linux OS (e.g. CentOS, openSUSE), this guide doesn't apply to you.
I'm hosting FFA warm-up and HvH(soon) servers in San Francisco, welcome to join by:
IPv4: 159.89.154.137
Ipv6: 2604:a880:2:d0::20ad:2001