Berlin privacy start-up ZenMate today announced it has expanded its online privacy tool to mobile.

The service, previously only available as a web-based Google Chrome plug-in, is now available to download on the Android and iOS platforms.  

ZenMate allows users to hide their IP address by changing their virtual location to somewhere else in the world.

The company said the mobile app is able to encrypt and secure all internet traffic on a user’s smartphone whatever their connection.

Simon Specka, ZenMate co-founder and CEO, told Techworld: “We wanted to bring the advantages of our browser extension to mobile to cover everyone - no matter which device they're using.

"We put a lot of effort into building an app that secures your device and provides the fastest connection possible at the same time."

ZenMate and other VPNs are seen as controversial by some people as they can be used, for example, by someone outside the UK in order to watch BBC iPlayer, or by someone in the UK to access the US version of Netflix, which boasts more content.

ZenMate currently has over four million users worldwide and recently won the Europas Award for Best Security/Privacy Startup of 2014.

Much of ZenMate’s early growth was in countries with restricted access to the internet, such as China and Iran, but in recent months it has seen significant uptake in both the US and Europe.

In January, the number of global sign-ups grew by more than 200,000, with a month-on-month increase in the UK of 72 percent and 71 percent in the US.