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London – A City Through Time: app of the day
What is it?
"Neither coffee-table book nor guide nor map, but a nearly endless fusion of all three in a digital application," according to developer Heuristic Media. That means 2,000 years of London in a 1GB app for iPad.
Not so much its sheer depth - although there are thousand of articles and images, along with audio tours, maps and video clips to dive into - but the way its clever timeline navigation helps you find your way through it all.
iPad - £9.99
London 2012 is all about the Olympic Games, but what about the last 2,000 years of history lurking beneath the shiny new stadia and flagwaving supporters?
If you're at all interested in the history of London, this iPad app is an essential purchase. It may be expensive in app terms at £9.99, but for your money you're getting a marvellous amount of information and imagery on the English capital.
Developed by Heuristic Media, London - A City Through Time pulls its content in from various sources.
There are 6,000 articles from a book called The London Encyclopaedia for starters; but then historical maps; spinnable photos of items from the Museum of London; 360-degree panoramic photos of landmarks; audio tours; videos from Pathe's archives; and stories from celebrities including Michael Palin, Renee Zellweger, Sir Alan Parker and, ahem, Jeffrey Archer.
It really is a wealth of stuff, which could easily be intimidating to trawl through. But that's why this app is so special: the developers have provided several ways to find your way through all the content, making it a treat rather than a tribulation.
Start with the multilayered timeline that you can swipe through by century, period (Tudor, Stuart etc), monarch down to individual years, with thumbnails popping up for specific events and articles. It works beautifully.
But there's also a Browse on Map feature where you zoom in and out of a Google Map, tapping on icons that represent articles. A separate History on the Tube section even gets you to choose a tube line, then shows you key entries for each station you travel through.
Meanwhile, a Life in London section drills into the articles and images by theme - public works, crime, sickness and disasters, and so on. Then there's a Notable Londoners section too, if you're more interested in people.
The audio tours are interesting - as long as you don't mind flashing your iPad while walking them, of course - and the Pathe videos are mesmerising, from Oswald Mosley and his blackshirts to the 1908 Olympics.
I could (and will) happily spend all summer using this app, and still not see everything it has to offer. It's absorbing, well-crafted and the latest glimpse at an exciting future for tablet book-apps.