I added rSAP support to the LineageOS sources for the Samsung Galaxy S II. It is contained in builds since March 29, 2018.
So if you still use this classic phone you no longer need my app, rSAP works right out of the box :-D
In case of problems use the forum. If I can find the time I'll also add rSAP to the Galaxy S III.
Yesterday I received the OTA update for my Galaxy S8 and it looks like Samsung included the fix for the Bluetooth bug - the phonebook app works fine. I hope other manufacturers will also include the fix in their Android 8.0 release.
For all others the problem shoud be fixed with Android 8.1.
Google modified the handling of the Bluetooth "Service Discovery" database (again) and now some cars can no longer be paired with phones using LineageOS 14. Strange enough everything is fine with the original Android 7, e.g. with a Nexus 5X. See here for a list of affected cars.
I'll try to add another hack to the Bluetooth driver to fix this problem, but it may take some time.
One user notified me that he managed to pair his Mercedes SAP V2 adapter with his phone by initiating the pairing from the phone. He touched the "MB-Bluetooth" device in Android Bluetooth settings, while the adapter was (unsuccessfully) searching for the phone. Maybe it works for others as well.
Google once again changed the internals of the Android Bluetooth stack, and guess what: it breaks my phonebook app. It is no longer able to properly stop the built-in phonebook service.
Today I found out that the latest Android source contains a change which once again enables my app. I don't have an idea when that change will be published in an official release or if there may be new Android 8 firmwares in the future which don't contain that fix. Simply check if your car connects to my app, if not you'll probably have to wait for the next firmware update.
And these problems all happen only because Google refuses to add a proper Bluetooth SDP API to the Android SDK. So they work their way from hack to hack. Sad...
It looks like the rSAP app is used in more configurations than I can imagine. I tried to run the new version on as many phones with a lot of Android versions and different SOCs, but it is still not working for some users. So I decided to publish two more updates to the app (trial and full version):
I'm sorry for all the troubles which the update caused. I hope this will not happen again...