When Microsoft announced windows Phone 8, Nokia said that no Windows Phone 7 model can be updated to Windows Phone 8 and it was believed that Windows Phone 7.8, which brings some Windows 8 features to older Windows Phone models, like the same new start screen, re-sizable live tiles, Wi-Fi tethering and improvements to the camera, would be the last update for those phones that started life at Windows Phone 7.

@gekatwitti @nikonorovivan Мы про Windows Phone тоже можем рассказать, если что =)

— Windows Phone Россия (@WindowsPhone_ru) November 13, 2012

Confirmed by a tweet from the official Russian Windows Phone Twitter page, there will be 18 months of support for Windows Phone 7.8 which will last through the middle of 2014. Which means that there is still updates coming to the current windows phones that already upgraded to 7.8.

According to the slide, the Next Update will be 7.X which means it might be Windows Phone 7.9 packing some improvements & bug fixes... Only minor updates.

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Since Windows Phone first started shipping back in Q4 2010, there have been two software updates: NoDo, which added copy and paste and CDMA support; and WP Mango, which added multitasking, a newer version of Internet Explorer, and a whole bunch of UI tweaks. Lately, We've been hearing that there's a third update to Windows Phone called "Tango".

Chinese site, WPDang, is reporting that the Tango rollout will begin as early as this month (April). Soruce also says that Microsoft's intentions are to update 90% of the currently available Windows Phone handsets to Tango by the end of June.

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Microsoft has some major changes in store for Windows Phone 8, we have learned, which is the version of the platform currently being referred to by codename Apollo. Thanks to a video hosted by senior vice president and Windows Phone manager Joe Belfiore at Nokia, a number of WP8 features and themes have now been revealed.

Hardware changes

According to Belfiore, the overarching theme with regards to the Windows Phone 8 hardware ecosystem will be scale and choice. Specifically, Apollo will add support for multicore processors, new screen resolutions, and removable microSD card storage. It is clear that Microsoft is addressing one of the platform pain points, which is a perceived inability to compete in spec sheet comparisons with the iPhone and Android-based devices.

NFC

NFC radios will also be supported, with Belfiore placing specific emphasis on 8's push into contactless payments. The "Wallet experience," as he calls it, will have the capability to be carrier-branded and controlled, either by a secure element on the SIM card or utilizing hardware in the phone itself. In addition, tap-to-share capabilities will reportedly work across multiple platforms, allowing desktops, laptops, tablets, and phones to all share content.

Windows 8 integration

Windows Phone 8 will not just share a UI with the next-generation desktop and tablet OS, apparently: it will use many of the same components as Windows 8, allowing developers to "reuse by far most of their code" when porting an app from desktop to phone, according to Belfiore. He specifically mentions the kernel, networking stacks, security, and multimedia support as areas of heavy overlap.

Moreover, Windows Phone 8 will reportedly scrap integration with the desktop Zune client in favor of a syncing relationship with a dedicated companion application. In other words, Microsoft is bringing back a richer version of ActiveSync after letting that program die out for the most part.

The powerful messaging integration is one of the best features of Windows Phone and an alleged screenshot from the upcoming Tango update shows Skype and Google Plus integration into the messenger hub.

After Microsoft acquisition of Skype, it was pretty clear that we will see Skype added to WP7 arsenal but everyone expected that it will take until the next major version, Apollo, before it appears. This screenshot shows that the integration will happen sooner and will add Google social network to the mix.

We know that the next version of Windows Phone codenamed Tango, will reduce the hardware requirements of the OS so that it could run on devices with slower and cheaper hardware.

Now, Microsoft has announced that Tango will have support for additional languages as well. This is necessary for Microsoft if it intends to sell Windows Phone devices in as many locations as possible. Mango currently supports 35 different languages but Tango is expected to take that number to 120.

Microsoft has also said that with the next release, developers will be able to develop apps and games for the OS using C++, although it is unclear whether next release refers to the next version of the OS or the SDK.