With latest image it should this easy to start use Pinephone beta edition as phone with Maemo Leste: - put sdcard with Maemo Leste (image wrote with dd) in sdcard slot. - start your phone (first boot sometimes have to start two times) - write you SIM-card-pin - Call with Sphone dialer icon or write SMS with Sphone New SM- icon (both apps comes with image) btw. this answer was wrote with Pinephone Keyboard.