However, until recently, Microsoft did not report anything about the limitations that exist because of the low-end devices, such as less memory RAM (256MB) and the slower processor. This changed in the page How-to's partners and now confirmed several limitations:
Some applications do not work if your phone has a memory RAM 256 MB.
You will not be able to manage podcast subscriptions from the phone or watching video podcast, if your phone has a memory RAM 256 MB.
You will not be able to automatically upload photos to SkyDrive, if your phone memory RAM is only 256 MB.
You will be able to use the Local Scout, if your phone has RAM memory only 256 MB.
Some HD video codecs will not be supported if the phone memory RAM is only 256 MB.
In addition to limitations in Windows Phone Tango brings with it several new features such as ability to attach videos and photos in text messages, or export contacts to a blank card SIM.
Worth to watch the following video site WindowsPhoneHacker, showing the major features of Windows Phone Tango in an emulator: