Today I installed the Android M preview on my Nexus 5 to check if there are any problems with my apps, and experienced a strange surprise: Android M supports rSAP. Well at least it supports the Bluetooth profile, but I could not really make it work. Maybe I messed up something on my phone, maybe it's simply not finished. But it seems Google at least recognized that rSAP might be a nice feature!
So my phonebook app still works with the Android M preview, my rSAP app doesn't, because the built-in rSAP blocks it. Let's see what will happen in future updates.