Have you try to use the resized feature of some apps? Like calculator and calendar ... the app resized is going to be floating over your screen and you can move it wherever you want.
Posted via the Android Central App
You can try to configure the bubles for messages. When you are on the messages window go to Settings then Display section. There you can customize the bubble style, the background, check it out!
Try to restart the phone ... that happened to me sometimes the messages notification sound goes off. Also you can set vibration on for notifications.
Sent from my SAMSUNG-SGH-I337 using AC Forums mobile app