Ok so this is a curious little problem I have. I recently flashed CM 12.1 on my S4 and since then I don't receive any notifications from apps like Bleacher Report, Snapchat or Instagram when I'm not using my phone. However, when I am using my phone I see notifications on Snapchat at least pop up. I tested this my sending myself a snap and voila saw the heads up notification say I had one. But curious thing is, this notification would not arrive if I wasn't using my phone and had it set down somewhere else. I have again tested this by having a friend send me a snap while my phone was set down and when I picked it up later, didn't see a notification. Same thing with Instagram. It's driving me nuts. Can anyone help me with this? I have read around and some people suggest this may be a problem that happened while restoring using Titanium backup but I cannot see why it would only affect certain apps. Facebook notifications work just fine. Fotmob (a soccer score app) works just fine. It's just SnapChat, BleacherReport and Instagram (at least those are the only ones I have noticed).