Just as expected, Leap's prepaid subsidiary Cricket Wireless has become the first U.S. network carrier to offer Apple iPhone on prepaid terms. The carrier is offering iPhone 4 and iPhone 4S on discounted prices. Virgin Mobile USA is also joining the prepaid iPhone launch party on June 29.

Cricket Wireless on Friday began selling iPhone 4/4S, in both white and black variants, on prepaid terms through select stores. Cricket said that buyers, particularly interested in iPhone 4S, were lining up even before stores were opened in the morning.

The carrier is offering 16GB version of iPhone 4S for $499, which is $150 lower than price for unlocked version of the smartphone. On the other hand, iPhone 4 is trading at the price of $399 for 8GB model. The carrier offers only one price plan for prepaid iPhones, a $55 Smartphone Plan giving unlimited calls, text messages and data. The data speeds will be throttled to 100 Kbps after users consumes 2.3GB of data within a month.

Sprint's Virgin Mobile USA is also in the queue to offer Apple iPhone on no-contract terms. The carrier will begin rolling out prepaid iPhone June 29. Virgin Mobile will sell 16GB version of iPhone 4S for $649 and 8GB version of iPhone 4 for $549. There are no discounts when compared to what Apple charges for unlocked version of those models, but users will get cheaper monthly plans starting at $30 per month.

At $30 per month, users will get 300 minutes of voice calls with unlimited messaging and data. With $40 per month plan, free voice calls increases to 1200 minutes, while the Everything Unlimited plans costs $50 a month. Like Cricket Wireless, the full-speed Internet access is only valid until user consumes a certain amount of data. The bandwidth will drop to 256 Kbps after 2.5GB of data cap is crossed.