Hello Beth,
That is not MobileSheetsPro popping up the ad, I assure you. As long as you downloaded the app through a legitimate app store such as Google Play, then there should never be advertisements. If you downloaded the app through a random third party store or through an unsafe link on the web, then all bets are off as someone could inject adware into the APK potentially. If you did install the app in the normal fashion, then you most likely have adware installed on your device. Please go through your list of installed applications and uninstall any that are suspect.
Mike
That is not MobileSheetsPro popping up the ad, I assure you. As long as you downloaded the app through a legitimate app store such as Google Play, then there should never be advertisements. If you downloaded the app through a random third party store or through an unsafe link on the web, then all bets are off as someone could inject adware into the APK potentially. If you did install the app in the normal fashion, then you most likely have adware installed on your device. Please go through your list of installed applications and uninstall any that are suspect.
Mike