Android suddenly pops up ad Suddenly my Android always pops up this ad that always in that position, even sometimes a video ad, when I wake my phone from sleep. Anyone has idea? 

When I open the recent used app, it displays the correct recent used app.

I have tried uninstall my but no luck:


  
  FF Record Keeper
  3rd party theme
I advice you to try and find which applications are running by using a program that displays your current processes. One of those will be the adware. You could also try and install some android anti-adware blocker, or even cut out the banner with an image editing program, make an image search and find which program or advertisiment the image matches, then you will know which program it is and you can find instructions how to remove it. 

If you install termux you can run the command ps -al|more and paste the output, then we will see which processes are running.