In a recent leak of Microsoft documentation of Windows Phone 7 we learn a few technical bits about the operating system. To start, we confirm that WP7 is based off of Windows CE 6.0, meaning that it has a 32-bit kernel and thus can addresses 4GB of RAM at the most (it would be a difficult to argue that a smartphone would need more than that anytime soon, so 4GB seems reasonable).
Also in the documentation we learn that you must enter a Windows Live ID into your phone in order to use it. This is more strict than Android and iPhone which require you to enter a registered account only if you’re attempting to use the application store. It’s likely that when Windows Phone 7 comes around, Zune Pass users will be able to associate their Zune account with a Windows Live account so you won’t need to sign into two accounts.
In terms of application development, there will be two types of apps: those that are “light” and web-based using Silverlight (think Twitter clients, etc), and those that are more heavy (like games) that use XNA. Those coded in XNA will also be cross-platform apps, being able to run on Xbox, Zune, and possibly the PC (with a bit of work).
In terms of the supported wireless protocols, Microsoft has Windows Phone 7 covered with all present and future standards. This list includes: GPRS (1G), 1xRTT (1.5G), EDGE (2.5G), UMTS (3G), EV-DO/Rev A (3/3.5G), HSDPA (3.5G), WiMax (4G), and LTE (4G).
For storage, Windows Phone 7 will have a unified storage system, meaning that phone ROM and any external storage will be bundled together for storing apps and settings. That raises questions about how easily you’ll be able to swap storage cards. If you remove the card, you’ll see the following message: If the Secure Digital card is removed, users can lose their data and the phone may not function normally.