Alongside mobile payments, O2 Wallet also allows customers of any mobile phone company to compare prices, and shop for goods on their smartphone.
The digital wallet service can be used by all UK mobile phone users, not just O2, and is available as an app on devices running Apple iOS, Google Android and BlackBerry OS 6. O2 said that it is working on a version for Microsoft's Windows Phone.
Working similarly to Barclay's Pingit, the Money Message part of O2 Wallet enables consumers to securely transfer funds from £1 to £5,000 to any UK mobile phone.
O2 Wallet is designed as a digital extension of existing debit and credit cards, making it quicker and easier to pay for goods. Customers can load money onto the app at more than 30,000 locations, including O2 stores, PayPoint and epay retail outlets.
The app also enables users to shop for goods with a "comprehensive barcode and search engine function", which can compare the prices of millions of branded goods at more than 100 online retailers.
There will be a variety of daily deals and discounts offered via the 'My Offers' icon, including launch partners Debenhams, Comet, Sainsbury's Direct and Tesco Direct.
"O2 Wallet delivers the benefits of mobile money to more UK consumers than any other product or service currently available," said James Le Brocq, the managing director at O2 Money.
"With O2 Wallet, it's easier to transfer money, track expenditure and pay swiftly and securely, all using your mobile. We believe it will transform the way people manage their finances and spend money."
A transaction history helps users keep on top with their account and payments records over 12 months. O2 said that the app will "evolve" to incorporate the new Near Field Communications (NFC) mobile technology in future to enable contactless payments direct from a handset.
Other future planned services for O2 Wallet include top-up mobile airtime, and the opportunity to buy train tickets.
Security concerns are addressed by the fact that no card or bank details are stored on the app, and all payments are based on pre-pay systems.
"We recognise that security is absolutely key. O2 Wallet has been trialled internally for months and has undergone extensive 'stress-testing' with security experts," said Le Brocq.
"In additional to PINs and passwords, all personal details and financial data are held on remote central servers rather than on the mobile device itself. This, we believe, is the safest and most secure way to deliver mobile payment services."
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