Smartphone owners who use wi-fi on the go are increasingly vulnerable to fraudsters.

The amount of mobile malware is rising fast, with a 22 per cent increase last year on 2010, according to a McAfee Antivirus study. Much of this malware is spread over public wi-fi networks and by unregulated apps with phones running Android most vulnerable.

The latest smartphones are pre-configured by several mobile networks to automatically connect to wi-fi hotspots such as BT's Openzone. Hackers then set up bogus wi-fi hotspots.

Once a connection is set up, information passing through the gateway, such as credit card and bank details, can be read and downloaded to a laptop by the hacker.

"Ensure that your phone isn't set to automatically log on to wireless hotspots," says Jason Hart, a former ethical hacker and MD of security company Cryptocard. "This might appear convenient, but it doesn't take much for a hacker to set up a rogue hotspot and hack your phone, pilfering all your information and passwords."

Turn off your wi-fi and Bluetooth when you are not using them and make sure to update your smartphone or tablet's operating system as often as you can, as this usually updates the built-in security of your device. A mobile anti-virus package like PhoneGuard Mobile Security ( will offer additional protection.

Finally, don't forget the physical security of your phone or tablet. Don't store sensitive information on it and use a password or PIN so that the average snooper can't access it if it is lost or stolen. Consider an app service that lets you locate, lock and wipe your device if it is lost or stolen. Apple offers Find My iPhone. Other makers offer similar services.