how to stop installing unwanted apps

[AC Question]

my android in the unwanted apps are installing without my permission like 9apps apus launchar and magic launchar...

 

[B. Diddy]

Welcome to Android Central! Does this happen in Safe Mode as well? On most Android devices, while powered on, press and hold Power until the Power Off menu appears. Press and hold the Power Off selection until the Safe Mode prompt appears. Tap OK.

If it doesn't happen in Safe Mode, then some app you installed probably carried some adware that is responsible--uninstall your apps one by one until this problem goes away. If it persists in Safe Mode, then it's probably malware that has installed itself to the system root, which can be very difficult to get rid of.