Tell them you don't like it, friends should at least accept your "weirdness". I still maintain that true friends should think alike you from the beginning in major things, but those are rare.
Again, another occasion to be taken as a ravaging lunatic and getting
faces and answers like this:
"ooh but I MUST check/answer/post facebook/twitter/SMS every 10 minutes! How can you not understand that I NEED it? You're HURTING me by asking that, you MONSTER!".
And that is from true experience (a bit spiced up for dramatic reasons).
Or invest in a cellphone jammer.
Really, it's cool to see that you are different from the masses, for a while, then you realize how lonely you are (even when in the middle of a group of "friends"), and you wonder how you will ever
manage to find a decent partner that isn't like this.