Verizon has officially launched their prepaid smartphone data plans. There are two plans, an unlimited plan that costs $30 per month (on par with AT&T's original unlimited iPad prepaid plan) and a 25 MB, $10 per month plan. As is the case with prepaid plans, there is no contract obligation, so you can cancel the plan at any time, and you are billed at the beginning of each month. The data plan costs are in addition to voice and text messaging costs, and you will need to buy the phone at the full retail price.The prepaid data plans are available for all of Verizon's Android phones, Palm Pre and Pixi Plus, and most of Verizon's recent Blackberries.

Verizon's announcement is the second pre-paid announcement this week. On Monday Clearwire announced prepaid plans for their 4G WiMax data service at $50 per month, $20 per week, or $5 per day. The service works with two devices, a $149 WiFi router and a $99.99 USB stick. The service only works on the 4G network, so it will not work in areas where there is no WiMax coverage. Last month Virgin Mobile U.S., which is a subsidiary of Sprint, launched a $40 per month prepaid data plan for a WiFi router and USB stick. The Clearwire and Virgin Mobile plans only require paying for data service each month and can be stopped at any time, while the Verizon plan announced today requires voice minutes. Personally, I would love to see Verizon extend their prepaid plain to their WiFi router.

Apple may legitimately claim to be the catalyst behind the lower priced prepaid data plans. When they launched the iPad 3G + WiFi model it included an unlimited monthly prepaid plan at $29 per month. At the time that AT&T iPad data plan was the cheapest monthly price for unlimited data. Several months later, however, AT&T changed the plan to the current one that charges $25 per month for 2 GB of data. The change was part of a broader AT&T initiative to eliminate unlimited data plans, and at the time speculation was that the other carriers would eventually follow suite. The Virgin Mobile, Clearwire, and Verizon plans all have unlimited options at reasonable prices making me wonder whether the carriers have decided to let AT&T hang out on the limb as the only carrier without an unlimited data plan.

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