this "adds resale value" by buying options idiocy that people keep repeating on this board is amazing.
why doesnt the OP just not buy the tech package and leave $3100 in cash in the trunk. it'll add $3100 to resale value.
it obviously sounds like he will have very little use for tech package. and even if he did get a smartphone in the future, you'd figure it might not be worth betting $3100 that the added "joy of use" a tech package would give him should he get a smart phone could possibly be worth getting the tech package now, seems like a poor bet.
it sounds like he's more or less made up his mind as it is and was just asking the board's opinion just in case there was something he had miss that would merit getting the tech package.
my suggestion for the OP (given he is trading in a 2 year e90). if you like getting new cars fairly often, save your $3100 and put it in the "next car after the F30 you are about to buy" mutual fund. $3100 in 3 years at 4-5% even is like what $3500 towards say a 2016 m3.