If you read all the threads in this post, many say they feel the system is falling asleep, others say they can't get the phone app to work but the web app works. If your system is falling asleep (which I am convinced is the issue here) it won't matter how you try to connect to the system, it won't find it. My friend has the 12" screen and he doesn't have any issues. My 8.4" system hasn't worked properly since I got the truck. BTW, If I select "Send & Go" app in the truck, it wakes up the system the same as SOS. Systems goes to sleep about an hour after I turn off truck.