People that stacked Focus
My website-blocking app of choice You can set up recurrent blocking schedules (I block Facebook all week except for 2 hrs on Sunday) And make 'block lists' of different websites/apps (I activate my 'Work' list to block Twitter and messaging apps)
System-level blocking of any websites or apps you find distracting. Replaces sites with motivational quotes. Has features like scheduling, password lock, and preferences lock for those tempted to just switch blocking off.