Convey allows users to register and log in with just a phone number and a unique code sent to that number. Once users are in the app theyre able to create events, add viewers and editors to those events (through their phone contacts), post updates with pictures (via photo or camera roll), and then event viewers are notified of updates via SMS as they come in.
Event viewers can see event info, updates, photo gallery, etc. Event editors can make changes to events, invite others, etc.