FreedomPop, the free, no-contract carrier that uses Sprint’s network to provide a service for its customer base, has added both the iPhone 5 and the iPhone 4 to its line of supported smartphones. Plus, a new iOS app from FreedomPop now also allows customers to send free calls and text messages to other users.

Customers can bring an iPhone 5 or iPhone 4 to FreedomPop and use 200 minutes, send 500 SMS messages, and access 500 MB of cellular data on its free monthly plans. The carrier will be selling Apple’s iPhone 5 directly to customers, too, for $349; though it’s not selling the iPhone 4, folks with compatible handsets can bring their iPhone to FreedomPop and use the smartphone on the carrier’s network.

FreedomPop’s iOS app allows users to make calls and send messages free of charge, though as 9to5mac explains, details on the process are scarce. FreedomPop did explain, however:

With the launch of its new iOS app, FreedomPop allows any iPhone user stuck in an existing contract to save hundreds of dollars per year by downgrading their voice plans and leveraging FreedomPop’s free voice and text service directly from their existing phone. Today, any iPhone, iPad or iPod user can download FreedomPop’s new communication app, which provides free calls, texts and voicemail. Customers also have the option to port their existing number to FreedomPop or select a new one. For the new iOS app, visit our page on the iTunes store.

There’s also an unlimited plan available from FreedomPop, and this removes the 200-minute, 500-text cap on the carrier’s free-to-use plans; this’ll set customers back $5 per month.

For more information on using an iPhone 5 or iPhone 4 with FreedomPop, head over to the carrier’s website. We’ll keep you updated with further information as we receive it.

In the meantime, see: Apple Updates Its MacBook Air: New Devices Now Cheaper, Faster, AppAdvice International: Stonehenge, Strong Sales, iTunes Connect And More, and Apple’s iPhone 6 Could Be As Thin As The Current-Gen iPod touch.