While Windows Phone contains many new features, a number of capabilities and certain programs that were a part of previous versions up to Windows Mobile 6.5 were removed or changed.[1][2] Until Windows Mobile 6.5, the previous version did always cover the complete feature range of the predecessor version.
The following is a list of features which were present in Windows Mobile 6.5 but were removed in Windows Phone 7.0.
Calling
The list of past phone calls is now a single list, and cannot be separated into inbound, outbound or missed calls[3]
Sync
Windows Phone does not support USB sync with Microsoft Outlook's Calendar, Contacts, Tasks and Notes as opposed to older versions of Windows Mobile with Desktop ActiveSync.[4][5] Syncing Contacts and Appointments is done via cloud-based services (Windows Live, Google, or Exchange Server), and no method to sync this information directly with a PC is provided.[6] Third-party software, such as Akruto Sync, provides some of this functionality.[7][8] A petition to Microsoft was filed to reinstate USB sync for Outlook.[9]
^Windows Phone 7 does not support Office documents with security permissions[32]
^While the older Windows Mobile phones supported the full range of Microsoft Exchange Server policies, Windows Phone 7 only supports a small subset of Exchange features.[34]
^Exclusive interview with Joe Belfiore, corporate VP of Windows Phone. Engadget. 19 July 2010. Event occurs at 06:30. Actually, as a general matter, there are a whole lot of companies that we're working with pretty closely to figure out what additional capabilities developers want and need to add great new scenarios, and so multitasking is a good example of one we're already talking to people about, we're looking for the right way to implement it. So that's something you'll see come from us at some point.
^Windows Phone 7 supports upgradable storage via an SD card; however SD card memory is merged with the phone's internal storage, and changing the SD card causes the phone to reset to factory settings[26][27]
^Seamless voice-to-video call switching with LTE: "... the only Android phones that support UMTS video calls are the Samsung Galaxy series of phones. Other than that, only Symbian and Windows Mobile (not Windows Phone) phones support UMTS video calls."