After years of me banging on about how they were poised to take on in the UK - it looks like they've made it.

The advert is a pretty good start. I'm a bit confused about why it says "Use your iPhone or Blackberry to scan the barcode" when both Android and Nokia also have barcode readers (I guess Windows Phone 7 will have one too).

I left this comment on the site.

Looks really good. Glad to see a mainstream brand like Tesco using QR Codes.

One thing - would it be possible to point to a mobile version of the site? The page that's linked to is a bit heavy - especially if you're only getting 2.5G speeds.

It might also be worthwhile customising the bit.ly URL to be a bit more meaningful. For example, I've just created http://bit.ly/TescoCOD which links to the same page but looks a bit nicer when scanned in.

It's great to see QR codes finally start to break into the British mobile scene. With a little more thought and effort, retailers can really harness the power of these little squares of joy.

Something that will particularly interesting over the next few weeks is seeing the response rate to the advert. Luckily, bit.ly provides statistics for all the URLs it generates. So, by visiting http://bit.ly/aefZn7+ we can see, more or less in real time, the effectiveness of the campaign.

Fun times ahead!

Failure 1 - Targeting

This version of the Tesco shopping app is only available on Nokia phones. Nothing wrong with that - Nokia are still the biggest phone seller on the planet. So why allow the advert to be shown to Android users? It will annoy users, reduce your CPM, and make users less likely to click on adverts in future.

Failure 2 - Sizing

This is the full resolution on the advert.

(full resolution)

168*28 is barely enough to contain all the information you want to impart - let alone make it look attractive. The Tesco logo is tiny and indistinct - the wording blurred and hard to read.

Failure 3 - Mobile Friendly

Here we come to the failure that we see so often. A lack of mobile friendly landing page.

Responsibilities

Guardian needs to make sure its ad-server are only showing adverts relevant to the user viewing the site. The ad-server needs to make sure its adverts are scaled correctly for different phones. Tesco needs to ensure that its advertising agency is buying advertising space correctly. Nokia needs a mobile friendly page for non-Nokia devices.

Lost Opportunity

Just think what Nokia could be doing with this landing page for non-Nokia phones.

• Show off the amazing capabilities of the app.
• Display screenshots of the app.
• Tell the user which phones the app works on.
• "Don't have a Nokia? Take a look at these awesome devices!"
• "Here's a map to your nearest Nokia store..."
• "Get £100 off any Nokia device when you trade in your Android phone!"

You know the crazy thing? They do most of these things already!

If you try to download Ovi Maps on a non-Nokia - you get this page?

Nokia really need to have a joined up strategy for how they deal with users who have competitors' devices. Both the Guardian and Tesco need to do some quality control on their adverts and ad servers.