I updated my Samsung galaxy s3 to 4.3 a few days ago, and ever since then, push notifications for the built in messaging app hasn't been working. My phone doesn't ring, the icon doesn't appear in the back on the top of the screen, and the lock screen doesn't show the previews. I have to keep manually checking if i have new texts by opening the app, which is annoying and inconvenient. The sound works for other apps so I know that sound isn't the issue here. Does anyone know how to fix this?!
Could it be, that for some reason--aliens, loch ness, etc.--that some of the apps have "show notifications" checkbox unchecked? To check, go to Settings->Aps->whatever SMS app and see if you have a Show notifications checked.
Also, have you tried using Hangouts as a replacement for texting?