A new mobile messaging app called FireChat allows smartphone users within 10 to 30 meters of each other to stay in touch when there's no Internet connection or cellular service.

FireChat uses a technology called "wireless mesh networking" that enables communication "off the grid." The app was made by Open Garden, a San Francisco startup with 10 employees. Open Garden released a FireChat app for Android phones last week.

The technology could someday enable online communications in remote areas or disaster zones without Wi-Fi or cellular signals.

Firechat is an open-source, real-time chat widget that offers fully secure multi-user, multi-room chat with flexible authentication, moderator features, user presence and search, private messaging and chat invitations, among others.

Wireless mesh networking is a communications network made up of radio nodes organized in a mesh topology. It could be used someday to connect thousands of devices with built-in radios and make it possible to be online without having to pay for the access.

Conversations in off-the-grid networks can't be easily hacked into by spies and mischief makers or shut down by governments trying to stifle free speech.

"We trying to create networks built by the people for the people," said Micha Benoliel, CEO of Open Garden.

Google is among the big Internet companies intrigued with mesh networking's potential to bring more of the world online. FireChat could be an even hotter commodity on Android. It's already has been installed on more than one million iOS devices.

The core data layer under Firechat uses Firebase for real-time data synchronization and persistence.