Zip Phone has developed a new Android app that allows users to make secure, Wi-Fi enabled phone calls, without using any data.

According to the company, the app has to be installed only once and is an ‘invisible apps’, which operates in the background, and only launches when required.

Zip Phone founder Anuj Jain was quoted by Tech Crunch as saying: "There are dozens of voice-over-IP applications available, Skype,Viber, and LINE being the big ones.

"What makes Zip Phone different is that it’s just ridiculously easy to use."

Unlike similar apps, Zip Phone does not require placing a call, launching the app, signing in, check who’s online, and then dial from the app.

Jain added: "With Zip Phone, you just need to have it installed on your phone once, and that’s it.

"My philosophy is that you should never have to look at my app again."

In a bid to beef up security, the app encrypts calls via a blend of encryption processes including RSA and 256-bit AES encryption, with the makers claiming even they can’t snoop on calls.