and maybe some other phones as well? I just had a popup message appear on my Note 4 stating that IF 6.x is installed on the phone, that I will loose some of the features that are extremely important to me. What would that be? Call Recording. I am using ACR " Auto Call Recorder" and it is the only call recording app that has been faithful, works every time, AND also records both sides of a conversation when a Bluetooth headset is used with your phone. All the other call recording apps that I tried, and that was a whole bunch of them, were not stable and could not be relied upon. I lost some extremely important information when they failed to work and record the "incoming caller's voice" when I was using a BT headset. All I would get on the recording was my voice.... argh! * Call Recorder - Auto Call Recorder Free - Android Apps on Google Play So, with this little admonishment, and a word of warning, I hope this will do someone a bit of good. see the picture for more info. https://bitbucket.org/copluk/acr/issues/570 Samsung S5 and Note 4 with Android 6 copluk repo owner created an issue 2016-03-28 Call recording on Samsung S5 and Note 4 on Android 6 might not work! We started to receive reports from people who had received official Android 6 update to their Samsung 5 as well as Note 4 and investigating. It looks like Android 6 for Samsung S5 and Note 4 either knowingly or due to a bug does not support call recording any more. This seems to be same with all call recording apps. We will update this issue as we get more information .