For most iPhone applications, why is this better than the built-in GameKit, which allows for peer-to-peer discoverability over bluetooth and WiFi without any active internet connectivity?
I could see an argument for cross-platform compatibility, as GameKit is iPhone-specific.
That said, is the service being provided sufficiently difficult to implement that it warrants paying (and relying on) an external service? How likely is it that an open source version of the server/client could be produced?
Two main reasons: 1) BT does not work quickly or reliably for ad-hoc connections. Have you tried using GameKit? It takes >45 seconds to ad-hoc pair (if BT is cold) and does not always work and 2) BT is very unreliable across platforms.
But requires an internet connection but is fast and reliable compared to the alternative. Time will tell if that is a more compelling compromise.
A lot of the applications using the Bump API are built on the cloud, so they would be useless without internet anyways.
I could see an argument for cross-platform compatibility, as GameKit is iPhone-specific.
That said, is the service being provided sufficiently difficult to implement that it warrants paying (and relying on) an external service? How likely is it that an open source version of the server/client could be produced?