Are there any apps in android that blocks users from accessing certain sites on which they spend too much time. i cant blockout whole internet for many reasons ranging from professional to domestic. i just want to ban some sites system wide across all browsers. like stayfocussed does on MACos or coldturkey does for windows. in googleplaystore i couldnt find any that were system wide. i am not looking for those apps on which can user can control and change the list of blocked sites at will. i need something which once blocks a site it stays blocked for that amount of time and there is nothing u could do about it.