Touch iPhone/iPod/iPad Transactions

I heard that there are applications that allow peo开发者_运维百科ple to do transactions by just touching there iPhones to each other. How is that archive via code in Objective C?

I beleive each phone has to detect the "bump" (using UIAccelermeter) and send an immediate notification of the event ot a server (perhaps with a timestamp and some geolocation info too?). Then the server matches up events that occur at the same moment, to determine the two devices involved. Then the server facilitates the transaction by sending each phone's info to the other.

take a look at the Bump API http://bu.mp/api.html as used in the Bump iPhone application. I haven't used it myself so I cannot say how easy it is to integrate but they claim it only requires you to add ten lines of code.

The way I would do it would be to have each device send the other their UID over bluetooth and then have them both send a message containing the other devices UID and their own UID to the server with a timestamp, then have the server handle the transaction.