Windows Phone 7 has been officially announced at a Microsoft press conference today.
We've already posted a raft of stories on the handsets, operators and more. You'll find them all below.
Windows Phone 7 news
Windows Phone 7 handsets
Windows Phone 7 handsets by network
Here are 21 things you need to know about Microsoft's new mobile OS.
1. The Windows Phone 7 release date is 21 October
As of 27 September, the latest rumours are that the Windows Phone 7 UK release date is 21 October - Microsoft has called TechRadar to a press conference on 11 October. so it seems likely that Windows Phone 7 will be officially announced then.
UPDATE: On 11 October Microsoft has confirmed the Windows Phone 7 release date as 21 October.
2. Windows Phone 7 phones
The list of Windows Phone 7 partners is plentiful. The initial partner list named was: AT&T, Deutsche Telekom AG , Orange, SFR, Sprint, Telecom Italia, Telefónica (they own O2), Telstra, T-Mobile USA, Verizon Wireless and Vodafone and manufacturers Dell, Garmin-Asus, HTC Corp., HP, LG, Samsung, Sony Ericsson, Toshiba and Qualcomm. Wowsers.
See the links at the top of the page for all the latest handset announcements or our Windows Phone 7 phones: all the handsets piece.
3. Windows Phone 7 operators
Windows Phone 7 devices will come to Orange, O2, Vodafone, T-Mobile and Three customers, although there is no mention of Tesco and Virgin Media, which run on those networks.
For more details, see Windows Phone 7: Which network is offering which phone.
4. Windows Phone 7 games
The impact of the Games hub will be crucial. Microsoft has confirmed that it will be easy for developers to port games created for the Xbox Arcade to Windows Phone 7.
Microsoft has also told TechRadar that it is aiming to offer more games with Windows Phone 7 at launch than it did on the Xbox 360.
5. It has a long way to catch up
Windows Mobile devices accounted for a mere 7 per cent of smartphone sales in Q1 of this year, according to Gartner, with Symbian leading the way with 44 per cent, RIM in second place with 19 per cent, Apple in third place with 15 per cent and Android in fourth place with 10 per cent of the market. It's a long way up.
6. Windows Phone uses Dorado
Dorado is the codename for the Zune software for the PC. And now, iTunes style, it'll sync content to your Windows Phone, too. After all, ActiveSync is rubbish, isn't it?
7. But there's no copy and paste
Can it really be true that Windows Phone 7 won't have copy and paste? Turns out that delivering the context-sensitive tools for handling information like phone numbers and addresses was part of the reason that the copy and paste feature of Windows Mobile didn't make it into version one of Windows Phone. Microsoft senior director Paul Bryan confirmed: "We ended up getting to the point where we said we need to deliver a great experience and there are certain things we can get done in this period of time and certain things we can't."
8. It's good for work and pleasure
Windows Phone has to keep the features that make it so appealing to corporates – compatibility with Exchange and Office, for example. But in Windows Phone 7, Microsoft may finally have found a way to balance this with the thirst for snazzy smartphone tech. Never mind getting two push email accounts on Android 2.2 or iPhone 4; not only will Windows Phone 7 let you have the two Exchange Active Sync connections, but Microsoft senior director Paul Bryan told TechRadar that you can sync as many EAS [push] email accounts as you like to your phone. "We can do more than two - there's no limit," he said, adding that he's syncing three accounts on his own phone.
9. No multitasking
The OS will process Microsoft's core integrated experiences, including music and phone calls, in the background, but not those of third-party apps – very much like the iPhone was before iOS 4. There will, however, be support for push-notifications so that third-party apps can send you updates and status messages when the app itself is not running. Multitasking will probably be implemented in a later version of Windows Phone, but Microsoft is currently choosing to be cautious in terms of battery life.
10. It's great with people
The People Hub is the finest way we've yet seen to bring all your communication together in one place, Oded Ran previously told TechRadar that Microsoft would enable social networks to implement their services.
11. High res screens are still the way forward - for now
You should remember that Windows Phone 7 will be only running phones with WVGA (800 x 480) screens - we like that level of resolution. But the problem is that that screen res can be a) heavy on the wallet and b) not necessary in some phones. So to that end, Microsoft will be adding HVGA (480 x 320) to the mix in the future, which means slightly lower res video, and apps will have to be rescaled to run on lower-pixelled screen. But Android has managed it with recent reboots, so there's no reason why Microsoft can't be successful with it as well.The Samsung Omnia 7 below has a Super AMOLED screen, too.
12. It's all about the live tiles
At a time when Apple's iPhone UI still holds major influence over the market (look at Samsung's Wave and other new handsets to see why), Microsoft has managed to at least mix things up a little. Taking the best aspects of the Zune interface and combining them with the dynamic tiled approach is clever – we're fans.
13. Search is central to the experience
As well as the Start button, every Windows Phone 7 phone will come with a dedicated hardware button for Bing, providing one-click access to search from anywhere on the handset. "A special implementation of Bing search provides intent-specific results, delivering the most relevant web or local results, depending on the type of query," says Microsoft. What that actually means is that if you search for "pizza" on a phone, it'll search local businesses for you first.
14. There will be plenty of ads
Windows Phone 7 is set to allow advertisers to push through info on their products through a platform called Toast. "(WP7 is) an extra move on our NUI (natural user interface). We're trying to get technology out of the way of people," said Kostas Mallios, Microsoft's general manager for Strategy and Business Development, speaking at the Cannes Lions International Advertising Festival in France.
15. Windows Phone 7 specifications
Windows Phone will have plenty of punch. As we saw at Microsoft's Mix developer event back in March, Windows Phone 7 will be able to draw from the phone's resources in a big way and still survive - which makes sense when you think it's going to have a 1GHz processor as a minimum in most devices.
16. Hubs are it
The People Hub is clever (even if it's not totally original). But we like the idea of gathering together content – after all gathering media together is basically what Apple does with the iPod app on the iPhone. Integration with third-party apps and services also marks a real departure for the OS, even if it may be seen as a necessary evil by some Microsoft internals. Windows Phone 7 includes six hubs including Office, Xbox Live and Marketplace for apps.
17. Developers will be well catered for
Devs will be able to take advantage of elements like multi-touch, the camera, GPS, push notifications and accelerometers to make cool new applications, while there's also full Silverlight support.
18. An improved Marketplace
Microsoft has decided to overhaul the Windows Phone Marketplace, so it will feature a panoramic design and 'active merchandising' to increase the discoverability of games and applications. Microsoft will now stop unlicensed third party apps from making their way on to WP7 devices. This means app vendors like Handango will have their noses put firmly out of joint - it's a significant revenue stream gone bye bye. The Marketplace will also support one-time credit card purchases, mobile operator billing and advertising-funded applications to increase the raft of options on offer - basically offering more ways to pay makes developers happier.
19. You can 'try before you buy' Windows Phone apps
At a recent briefing with Microsoft, TechRadar was told that one problem with free versions of applications on other app stores is people will install the trial, take a quick look then uninstall.
When asked to rate, the results are invariably low - therefore by placing both the free trial version of the app and the full price version together, the end rating will better reflect the quality.
Microsoft also promised us there would be "enough applications on day one of the Windows Phone  launch" and that no longer would the phone interface simply be a "sea of icons".
20. There's no memory card support
Here's a down side - there won't be any memory card support. Actually, there will be support for them, but you can't get to them. That's right - the two options will either be built-in memory, and gallons of it, with no memory card slot (think Nokia X6) or there will be a 'locked' memory card under the battery. Why? We have no idea. It seems that if you can support hot-swappable memory cards, you should. It just makes life easier for the end-user.
21. It'll sync over Wi-Fi
Apple, please sort this out. Microsoft has beaten you to the punch.
Liked this? Then check out Hands on: Windows Phone 7 review
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