Step 1: Visit LuckyPatcher website and download apk file and install on your android mobile phone.
Step 2: Open LuckyPatcher app, find a app you want to block or remove in-app google ads and tap on it you get pop up option as show in the picture.
Step 3: Tap on ‘Open Menu of Patches’ Option and select ‘Create Modified Apk File’.
Step 4: Select ‘Apk without Google Ads’ option,wait for app to build app without in- app google ads and after completion of build install it.(Uninstall original app before you install modified app.
Thats It. Have fun.