Virtual private networks (known in geek speak as VPNs) were first used to provide a secure connection for remote workers to corporate networks.
Now they're often used to access geo-blocked streaming services such as the US version of Netflix. A VPN provides an encrypted conduit to allow users to securely send/receive data.
Recently, they've being marketed toward smartphone users, with the main aim to protect people when using public wi-fi rather than geo-blocking.
But do you really need one? Well, that depends on how much you value your privacy and access to free internet.
Most public wi-fi networks are not encrypted which means others on the same network can eavesdrop on your web browsing.
Using the Wireshark utility at a hotel I recently stayed at, I was able to view the online activities of fellow guests also connected to the hotel's wi-fi.
Symantec has just released its VPN app, called Norton WiFi Privacy, which is available for both iOS and Android. It costs $49.95 a year.
According to Symantec's Australasian territory manager, Mark Gorrie, the app has advantages over offerings from lesser known competitors.
"Norton WiFi Privacy does not impose data limits or advertisements on users as a trade-off for services."
The app detects when your smartphone/tablet connects to an unsecured network, encrypting data and diverting it through a secure connection.
Anyone snooping should only see a stream of gibberish.
However, the app adds a small amount of delay into the mix. This was because I was connected to a range of Symantec VPN servers located around the world.
So is it worth the $49.95 a year?
If you use a mobile device for sensitive correspondence over public wi-fi a lot, it is probably a good idea.