The next version of Windows Phone is getting faster, opening up and - Microsoft has promised - won't suck your battery dry.

Microsoft on Wednesday unveiled changes in the version of Windows Phone codenamed Mango that will crack open the operating system so devs can finally work with smart-phones' camera data, compass and gyro, pivot and panorama, geo-location, ringtones and users' contacts.

The operating system, meanwhile, has been optimized to make applications run fast, gobble less memory and delivery "buttery smooth" scrolling. Execs unveiled the plans during Microsoft's MIX conference in Los Vegas, Nevada.

Microsoft corporate developer division Scott Guthrie, previewing code-level changes in Mango targeting devs, claimed that Microsoft is seeing applications running on early Mango builds use 25 to 30 per cent less phone memory than the current version of Windows Phone 7.

Other improvements will see image decoding no longer freeze the app while the data for the image is loaded, while garbage collection won't pause an application.

Guthrie said the code has been optimized without developers needing to change their applications.

Mango, expected in September, will feature TCP/IP sockets for devs building conversational applications like chat and IM.

Windows Phone Hubs, which group related data like music, are being integrated with Bing cards – templates that group related and relevant topics of information with your search returns. The change means when you search for something via Bing on a Windows Phone you'll be able to pivot across to applications on your phone that contain related information.

Windows phone program management corporate vice president Joe Belfiore used MIX to confirm and detail what we know was in the works: Microsoft will make Windows Phone's built-in SQL Server Compact Edition database open to use by third parties' apps. The database supports Microsoft's LINQ so you can query and save data in an application.

We knew, too, that multi-tasking and the ability for applications to run in the background were coming, but Belfiore explained how they'll work and how – theoretically at lest – Windows Phone won't suck the life out of your phone's battery.

Mango will come with APIs built in for background audio, file download and alarms so these are capable of running without the need for the phone's user having to do anything to activate them.

To illustrate them in action, Belfiore played a piece of music on an HTC phone running an early Mango build and had it continue playing when he navigated away to a different application. To illustrate the importance of file download and alarms, he demoed a Quantas airlines "concept app" working with location details and clock to alert him on when it's time to check in for a flight and provide updates on flight status.

Applications you move away from, meanwhile, will slip into suspend mode rather than sleep so you'll get instant resume - avoiding start-up delays - when you return to the app.

Microsoft's phone man reckoned that implementing background audio, file download and alarms in the operating system would save the phone's battery power.

Mango will feature a full version of Internet Explorer 9, complete with HTML rendering engine and JavaScript support. Belifore, though, tried to prove Windows Phone will display HTML5 pages faster than the iPhone 4 or Android, on a Nexus phone. Running a test application he claimed a frame rate per second of 26 for Windows Phone versus 11 on Android and two on the iPhone. IE9 is being juiced because it's using the same hardware acceleration that Microsoft has been boasting about on PCs.

Garnishing the whole event was a brotherly plug from Nokia, the phone giant that has agreed to dump Symbian, Qt and MeeGo on smart phones and install Windows Phone 7.

Marco Argenti joined Belfiore on stage to help convince Windows developers they should build mobile apps by talking "market" opportunity. Argenti said Nokia is "really committed" to its partnership with Microsoft, has the scale to reach hundreds of millions of customers, and is "working very very hard" to create the first Nokia Windows Phone. Argenti was billed as Nokia's "head of developer experience" but Argenti's LinkedIn profile describes him as responsible for media and games at Nokia, an empire that includes the Ovi Store.

To further convince Windows devs they should go mobile, Belfiore said they'll be able to sell apps for Mango in 35 countries, up from today's 16, and build apps in 36 compared to 30 now. It's not clear how much of this is down to the Nokia pseudo assimilation, but Belfiore said: "We are working with Nokia, who is strong in countries around the world." ®