Deletes last 3200 tweets which is all that shows up on any tweet archive site... so unless youre being investigated by the fbi or something you should be good with this app To the people that say it doesnt work make sure you update the Twitter accounts under your settings on your phone because if youve updated your password recently or something it might not work even though it shows your account on the app (usually it takes a while when deleting when this is the case and nothing actually gets deleted)