Usability 
MobiLuck, which started out as a Bluetooth based chat, dating, messaging and file sharing application now has a mobile web based social network. Like MocoSpace, Peperonity, Wadja, ItsMy, Multiply and several others it's a pure mobile play rather than a mobile front end to a web based social network. MobiLuck focuses on location and presence. The idea is to share your location with friends (and strangers if your feeling adventuresome) so you can meet up with them in the real world. When you log into MobiLuck you see a listing of friends and other users who are nearby. See someone you know or want to meet? MobiLuck lets you open a chat session, IM them with MSN or phone them. Optionally you can receive SMS alerts when a friend is within a certain distance (1km by default).
The mobile web based version of MobiLuck doesn't really detect your location . That's not really MobiLuck's fault, it's almost impossible for an off portal web service to obtain location data because of carrier policies. To share your location with MobiLuck you have to enter it manually.
11-Feb-2013: Site is down.