How to stop ads showing up on screen The phone is showing ads on the bottom of screen as well as on the top of whole screen 
I tried deleting the recent apps i installed 
I also tried disabling "show app on top" 
Is there any third party app that can scan the phone
Possible reasons: 

• Checkout Games that you installed recently.

• Check if you installed any app related to Wallpapers or lock screen category.

Because as far as i know Samsung doesn't have internal settings to show these horrible ads which covers the screen and affect their User Experience.

In previous cases 'Games' are at top which is causing these types of ads.