I have installed this app numerous times. It fails often, failing to pair to the hearing aids. I have rebooted. Reloaded, repaired, everything. I can't get it to load now. Phonak VIRTO M90 aids bluetooth to my Samsung S9+ phone just fine. I can adjust volume on the aids. The app allows me to adjust each side individually when it works. Other features of the app are possibly handy, but Virto M90s have numerous programs that they automatically select. The app is buggy and relatively useless to me.