Online payment service PayPal has rolled out a new feature that it hopes will increase the security on its users accounts. You can now choose to authorise every transaction via your mobile phone.

All you have to do is register your phone number on PayPal's website, then whenever you want to pay for something with it, you get sent an SMS with a special 6-digit security code in. To complete the payment, you have to enter that code, ensuring that it's really you paying for it.

The service doesn't cost anything extra, except for the cost of a single text message. Now that most people are on plans with near-unlimited texts, that shouldn't be too much of a burden unless you pay for everything with PayPal all the time.