Everybody loves to save a little here and there, and now Tesco Mobile wants to help by giving you money off your monthly bill without you having to do anything – well, much – more than use your phone.
Tesco just asks that you look at an advert when you unlock your phone. It comes through a third-party service called Unlockd, and it won't be every time you unlock. The estimate is that it will provide an advert every third time you unlock your phone.
If you're interested, you can download Xtras through the Google Play Store if you're running Android 4 Ice Cream Sandwich software and above. You won't be able to get this on iOS, but it will eventually come to Windows Phone.
Anthony Vollmer, CEO of Tesco Mobile, told TechRadar: "We'd always keep [adverts] optional. We'd never, ever make it compulsory. It's all about control for the customer.
"It definitely won't be for everyone – but for those who are up for it it's a great option to have."
When you sign up to Xtras you'll be asked for a few details from Tesco, including your interests, so you'll be served the right ads relevant to your taste.
It all ads up
The ads appear immediately on your phone when it's unlocked, and each is easily dismissible by pressing the cross in the top-right corner. You can even save ads for later if you're too busy to look there and then.
If you're getting a phone call or the alarm is going off, you won't get an ad served to you. You also won't see an advert when you're halfway through a text message – it's just when you first unlock the phone.
It's not all traditional static adverts either – you could sometimes be served articles from publications such as The Sun or The Times.
If you see at least one advert a day for 21 consecutive days you'll receive £3 off your phone bill at the end of the month.
Tesco contracts start at £7.50 a month, so you could bring that down to £4.50 a month. It won't count against your data allowance either – Tesco gives you 200MB extra a month for the service, to cover what it estimates as 120MB more usage a month.
Right now you'll only receive £3 a month, no matter how many ads you see, but CEO and co-founder of Unlockd, Matt Berriman, confirmed to TechRadar that the company is looking at paying according to how many ads you see.
Tesco's decision to offer adverts to customers is a bold step when networks such as EE and Three are both investigating aggressive ad-blocking.
Perhaps an even more interesting idea from Unlockd is the idea of a free smartphone, without customers being tied to a contract.
Berriman said: "What we're really interested in is that smartphones coming out of Asia – especially China – are as cheap as $40. We're now talking to different parties where we could say 'here's a free smartphone for six months'.
"We'd say 'pay with your credit card and we'll only charge your card if you delete the app', and after six months of ads you've paid your smartphone off.
"Take a SIM from wherever you want and that's a free smartphone. It doesn't have to be just cash or data – it can be other things."
Unlockd is also looking at its ads service giving you a discount on Spotify, Netflix or Amazon Instant Video.
That's all in the future though. Right now, you're able to save £3 off your contract just by downloading an app and seeing some adverts – it just depends if you want to take those few seconds out of your day to save what's only a little bit of money.
It's certainly not for everyone, but if saving money is your main interest this may be a choice for you.
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James is Managing Editor for Android Police. Previously, he was Senior Phones Editor for TechRadar, and he has covered smartphones and the mobile space for the best part of a decade bringing you news on all the big announcements from top manufacturers making mobile phones and other portable gadgets. James is often testing out and reviewing the latest and greatest mobile phones, smartwatches, tablets, virtual reality headsets, fitness trackers and more. He once fell over.