With cell phones continuing to morph into Swiss Army-knife-like devices, often combining a camera, music player and web browser in one small package, New York-based tech company MegaPhone figured why not add interactive game controller to the list?

MegaPhone develops easy casual games to play on large public screens for companies looking to provide an immersive marketing experience. The twist is that would-be players enter these games by calling a posted phone number and then using their phones to participate. Palm was the company’s first commercial client, using the tech in fall 2007 to tout its Centro handset. MegaPhone’s now looking to enter the kids promo space.

‘In some sense, we’re a highly optimized version of a voice mail system,’ says CEO and co-founder Dan Albritton. ‘But instead of doing what voice mail does, we just take all of the data – the keypad presses and voice commands – listen to it in real time, and pass that data along to games.’

So how does the tech come to life? Picture this: A person walks through a public space that sports a large TV, which urges passersby to phone and join in the video game. He places the call via cell phone and immediately becomes a gamer immersed in a kid-friendly battle arena, controlling his character in real-time with his mobile handset via keypad commands to shoot targets on the big screen. Alternatively, someone can talk into the receiver and their voice controls the gameplay.

The real-time factor adds an almost magical element to the tech, drawing users in, and what hooks them, says Albritton, is the novelty of gaming en masse in a public forum.

Companies interested in amping up their interactive marketing tactics have come to MegaPhone with their brands. A recent partnership with Canadian cable and wireless giant Rogers Communications resulted in a BlackBerry flip phone holiday promotion. The company created a game for one of the large screen displays in Toronto’s Dundas Square (editor’s note: It’s like Times Square, only smaller and colder, eh?) where Santa’s sack was moving side-to-side and ejecting the new BlackBerry model into a sea of virtual hands, which represented the callers. Players were encouraged to yell ‘Flip!’ into their phones, triggering a hand to pop up and grab the on-screen handsets.

The company is on the hunt for more partners, and is reaching out to the kids entertainment sector. Albritton is particularly keen on talking to property owners to develop licensed games that encourage deeper brand engagement. MegaPhone is currently in talks to bring its tech to the silver screen so kids could play games in movie theaters before the lights go down. Also of interest are the large digital score boards found in most major sports stadiums that could host games with up to 2,500 players partaking simultaneously.

It’s also in conversations with amusements parks and is looking to align with major TV networks to offer live-to-air interactive games.