Update: A 9to5Mac reader has chimed in clarifying that the new hotspot only offers the free 500MB plan on the new Sprint-enabled 4G service. For 3G coverage, users will have to pay an additional $3.99 per month:

Although their website and press release say the new Overdrive comes with free data every month, there’s apparently a string.  Apparently only the 4G data is free, see my email thread with customer service below.  This is wholly inconsistent with what their website or press release indicates… This tactic is as deceptive as when FreedomPop first went live. At that time, they said the devices were “free with deposit” but it now turns out that if you keep the device for 12 months or more, the deposit is forfeited.  That forfeiture is buried deep within the TOS, and not likely understood by consumers until it’s time to return their hardware.

Wireless provider FreedomPop, the company providing access to free monthly data plans through a number of hotspot devices and iOS device accessories, today announced it is expanding its 3G coverage through Sprint’s network to provide nationwide coverage to its customers.

“The biggest criticism with our service to date has been the coverage gaps in certain parts of the country,” said Stephen Stokols, FreedomPop’s CEO. “Starting today, FreedomPop users can connect to the Internet across the entire nation leaving no reason to continue paying high monthly Internet bills for Internet from large, expensive carriers.”

In addition to the network expansion, it is also now accepting preorders for its latest hotspot device dubbed “Overdrive Pro” (pictured above):

The FreedomPop Overdrive Pro becomes the company’s first device to run on Sprint’s network. The Overdrive Pro will allow up to five devices to connect to it and get speeds up to 8 mbps down. In addition to FreedomPop’s free 500 MB plan, users can also purchase a 2 GB or 4 GB 4G/3G plan with no contract or annual commitment at rates up to 50 percent less than major carriers.

FreedomPop offers users free data (with the option to purchase more) ranging from 500MB to 2GB per month through devices such as its $99 WiMAX sleeve for iPod touch or the recently announced $89 Burst 4G home wireless router. It also has an iPhone 4/4S case that is awaiting Federal Communication Commission approval and told us in February it plans to roll out LTE service and a new LTE iPad clip later this year.