Vonage staked out a first on Wednesday with an iPhone voice over IP app that uses in-app purchases. Time to Call (free, App Store) can make calls to real-world numbers by buying calls in blocks of 15 minutes. Prices range from 99 cents to $2 for about 100 common countries and peak at $10 for 90 more difficult to reach countries. As iTunes handles the infrastructure, users don't have to be Vonage subscribers and can pay with whatever they already use on Apple's store.
