A tutorial from the Michigan State University Amateur Radio Club (MSUARC, W8MSU) on how to use 'DVSwitch Mobile' on Android to reach their Allstar repeater.
https://msuarc.egr.msu.edu/how-to-use-allstar-instead-of-echolink-on-phones/
Thanks to #NT0Y for the hints on usage which were enough to get me a successful configuration; - no QSO just yet, I'll have to find a time for a net.
