Barclays has extended its Pingit app, which allows you to send money just by using a mobile phone number, to virtually any bank and building society current account customer.

The app was originally launched in February for Barclays customers to send money this way, though other account holders could register to receive cash.

Now, they can send money even if they don't know the recipient's sort code or account number.

How do non-Barclays customers sign up?

It's not as simple as sending money from A to B. Users will have to download the app, register and set up a mini-account with Barclays.

This will be linked to their normal current account. They can then move money between the two.

Users make and receive payments from the mini-Barclays account, which effectively becomes a pre-paid account they top up to use.

The only proviso is that your current account must accept payments via the Faster Payments system, which most do.

Any customer who only wants to receive money using Pingit doesn't have to set up a mini-account or download the app. They can register online, and if their mobile is linked to their current account, the cash will go straight in.

What do Barclays customers need to do?

They need to download the app, register, and they can then send and receive from their current account.

Who can download the app?

Pingit, which is free, is available from the Apple App Store, BlackBerry App World and Android Market.

How do you make payments?

The system links the user's current account with their mobile number, so those sending cash do not need the recipient's sort code or account number to send money, only their phone number.

Money is sent using the Faster Payments service, which enables electronic transfers to be processed within two hours, 24/7.

Payments must range between £1 and £300. The maximum someone can receive in a day is £5,000.

Is it safe?

Barclays says transfers are as secure as any other banking transaction. The app is protected by a five-digit code set by the user.

Senders and recipients will also be notified about sent, received, pending and cancelled payments via a text from Barclays.