I have used redmi note 3 before I purchased redmi note 4. I have already faced some problems with redmi note 3 first one is the heating issue phone will start heating when I use download in background or play music in background. Second problem is hanging issues I have never faced hanging until I used the dual app facility in this mobile but after I started to use dual apps every application started to hang. I can't launch camera or play music or browse net during hanging. It forces me to restart the mobile every time it hangs. Sound quality and camera quality is average.