Most computer users know that opening the wrong email on a PC can give a cyber criminal the 'keys' to your online life - and your bank account.
But far fewer of us are aware that smartphones such as iPhones and Android can pose just as big a risk.
A new campaign by KnowtheNet, ID Fraud Protection Month to educate people about this new kind of cybercrime. A test here alerts users to the risks of cyber attack.
More than 50% of us now own a smartphone, and 64% of us access the internet at least once a day.
But 'traps' such as fake wi-fi networks are now allowing cyber criminals to steal crucial information from phone users - and then strip their bank accounts.
Web pages that can wipe your phone
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'Free' wi-fi networks - the risks
Tricks such as creating fake wi-fi networks with familiar names like 'Cloud Wi-Fi', prompt a phone to connect automatically - and then allow criminals to 'read' whatever users do online.
Unsecured networks might seem like a great way to get free internet - particularly when abroad - but these are also commonly used to steal information.
Last week, an attack was discovered which allowed attackers to instantly wipe Android phones using a single web link.
But most attacks are built for a single purpose - theft. Cybercrime pays.
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Stolen phone? Change your passwords
Many smartphone users also keep personal details such as social network passwords and banking details on phones - and 44% of users don't use a password to protect their phones.
Of those who do, one in nine use '1234' - handing cyber criminals access to email accounts that can yield addresses, bank details and even passwords.
38% of GB adults online with a mobile device keep key personal data such as online banking details (4%) and social media passwords (18%) on their device, and 44% of all smart device users don’t even have a password to protect it.
Criminals have begun to target smartphones as an easier way to extract the passwords, identity details and bank details they need for identity theft.
'Fake apps' - the new wave of cybercrime
Fake apps are also rife on marketplaces such as Google's Play Store.
'Clones' of popular apps such as Angry Birds Space instead infect your phone with malicious software.
The only defence is to be wary about downloading apps - particularly free ones - from the store.
Some simply serve you annoying adverts. Others, though are far more sinister - adding huge amounts to your bill by dialing foreign numbers or using premium SMS services.
'Your smartphone is s sophisticated if not more than your PC,' says Norton's Director of Security Response, Kevin Haley, 'It has all the same information, it’s got your work information and your personal information.'
'It even has financial transactions on it. Why wouldn't the bad guys target it?'
'I once wrote a blog about Facebook - Facebook is the most popular network, so hackers target it with malware. Mean girls always pick on the most popular kid in school. Cybercriminals are the same.'
'What’s happening today, it’s very simple to take an Android app, decompile it, then insert malware that can steal information, rack up huge bills and even spam others with infected links.'