I think there's room for a Webservice/app focused on events only that defaults to using sms for people that don't have accounts. The idea being that people can

I think there's room for a Webservice/app focused on events only that defaults to using sms for people that don't have accounts. The idea being that people can optionally make accounts with just their contact information which they can then give people access to (this way contacts stay updated by everyone with access rather than local copies on everyone's device that goes out of date). The app would handle basics like RSVP, sending out SMS reminders for people, tracking number of people coming etc. Right now handling this over SMS and tracking it is a pain so people default to FB, but I think there's an opportunity here to get a foothold.