@TraderGary You’re conflating the notions of proprietary and universality and you’re missing the notion of openness. All three implementations are proprietary, because they belong to their respective owners. I don’t think anyone will argue that MFi is not a proprietary implementation because it’s owned and licensed by Apple and to my knowledge, the specification isn’t available to the public, so it’s also closed. ASHA is somewhat different. It belongs to Google and it’s specific to Android, but it’s an open standard, not closed like MFi. Any Android licensee can implement it. Phonak’s Bluetooth Classic implementation is also based on an open standard, but the Bluetooth standards are the property of the Bluetooth Special Interest Group. The BT SIG will probably develop its own hearing aid standard, which may or may not supersede either or both of MFi and ASHA.