London, Leeds and Northampton are the three UK areas where mobile phone owners are most likely to have their device stolen, according to a new report by an insurance company.
Protect Your Bubble, which specialises in insuring modern technology, found that in London 18% of insurance claims are for theft of a mobile phone, the highest in the UK. Leeds was second, on 16%.
Stephen Ebbett, director of Protect Your Bubble, said: "Gadget owners can never be too cautious.
"Everyday we cart around hundreds, or even thousands of pounds' worth of high-tech gear, such as smartphones, tablets, cameras and e-readers.
"This makes many of us prime targets for thieves. Should you be unlucky enough to fall victim to mobile theft, specialist gadget insurance will cover you by replacing your stolen handset.
"The good news is that we're seeing mobile thefts drop. So far, 9% of mobile claims we've received in 2014 have been for theft, compared to 11% for the same period last year.
"But that doesn't mean smartphone users should be any less vigilant. People can reduce their risk of being targeted by keeping their mobiles out of sight in public. Carry them in a pocket or bag with a zip, rather than your trouser pocket, or in your hand."
The survey covered the 30 largest towns and cities in the UK, and found that Dudley, in the West Midlands, was the safest place for mobile phone owners with less than 5% of the claims received by the insurance company being for theft. According to the data gathered by Protect your Bubble, users in their early 20s were the most likely to be victims of theft.
"Mobile users can safeguard both their data and finances by blocking their phones with their airtime provider as quickly as possible after a theft - so they don't end up paying through the nose for unauthorised calls.
"Good gadget insurance will also cover the cost of unauthorised calls," said Mr Ebbert.
According to the National Mobile Phone Crime Unit, there are more than 250,000 reported cases of stolen mobile phones each year, with the unit encouraging users to install tracking apps to help trace a device after it has been stolen.
A spokesman for the Metropolitan Police Service said: "The Met has seen significant reductions in mobile phone crime over the last year following a range of proactive prevention and enforcement across London.
"During the financial year 2013/14, mobile phone thefts fell by 14%, while robberies that involved the theft of mobile phones were reduced by 24%.
The Met's Operation Ringtone is proving its success in reducing mobile phone crime and has now extended nationally and to Europe in a new agreement of sharing intelligence about identified criminals and the volume of mobile phone crime through organised criminal networks.
"This culminated in a mass European day of action on 20 March 2014, with involvement from eight UK police forces, Europol and other law enforcement agencies. Activity continues daily however during this one day of action, officers made 120 arrests in London for offences directly related to mobile phone crime."
Under Operation Neptune, the MPS maps second-hand markets, negotiates a voluntary Code of Conduct for premises to record sellers' personal details, checks property with the National Mobile Phone Crime Unit and informs local police when stolen property comes into their possession. There are regular visits and audit checks by local officers. In excess of 1,000 retailers are signed up and engaging in the scheme across London."