Idle thought. My problem with this sort of mechanic, specifically on WoD games, is it winds up just being a tool for the equivalent of crappy bar RP/dating crap.
It'd generally be unwise to talk about the demon you fought the other night via text message, which means most messages wind up being--
+text Jane=Hey what's up?
Jane's brain - "I really have better shit to do than exchange some bullshit meaningless string of texts with you."
IMO, if you're going to do this, include some sort of MAGIC TECH GURU NPC that secures everybody's phones, so they can actually talk about shit and not worry about 'omg the masquerade' or whatever.