Company: Useful Networks https://www.sniffu.com/ [1]
Why It's a Top App: Texting "Where r u?" to find your friends is so passé--sniff them out instead. sniff (Social Network Integrated Friend Finder) is a permission-based mobile application enabling users to locate their personal contacts in real-time, anytime and anywhere, via SMS (the crux of its revenue model) or on Facebook, providing them a detailed map view of their friends' current locations. While clearly targeted for social butterflies, the sniff app emphasizes privacy, with all user behavior governed by principles of notice and consent. Multiple levels of security guarantee you're only found when and if you want to be. App developer Useful Networks also mails out multiple confirmation notices to new users reminding them they joined the sniff network and should be mindful of their status and permission levels. Hey--that is useful.
Links:
[1] https://www.sniffu.com/
[2] http://www.fiercemobilecontent.com/story/video-sniff/2008-08-19
[3] http://www.fiercemobilecontent.com/special-reports/skyfire-top-mobile-applications-2008
[4] http://www.fiercemobilecontent.com/special-reports/top-apps-2008
[5] http://www.fiercemobilecontent.com/special-reports/vz-navigator-top-mobile-applications-2008