I haven't got my new GrapheneOS phone YET, because my question is: can certain overseas calling apps ( like, Boss Revolution) be used without any interuptions or complications? I have business contacts in the UK and I'm calling from the U.S....i need a secure ( as much as civilian possible) phone that has a good encryption OS but won't hinder me calling overseas. Anybody know if Boss Revolution works with GrapheneOS? Thanks in advance, Reaper.