Windows Mobile 6.5 vs. Windows Mobile 6.5.3 vs. Windows Phone 7

	Windows Mobile 6.5	Windows Mobile 6.5.3	Windows Phone 7
Windows CE kernel	5.2	5.2	6.0 / 7.0?
Minimum resolution	None	None	WVGA
Skinnable Theme	Yes	Yes	No
Finger-friendly	No	Some  what	Yes
Multitouch	No	Basic	Yes
Capacitive touchscreen	No	Yes	Yes
Stylus	Required	Optional	None
Touchscreen keyboard	Unfriendly	Finger-friendly	Finger-friendly
Required buttons	Start	Start	Start, Back, Search
Style of application	Normal	Normal	Task hubs
Pane switching	Tabs	Swipe	“Pivot”
Browser	IE Mobile 6	IE Mobile 6	New, still IE-based
Zune integration	No	No	Yes
Xbox integration	No	No	Yes
Social networking	Apps / Skins	Apps / Skins	Built-in

As you can see, Windows Phone Series 7 improves and adds a lot of things that the two previous Windows Mobile operating systems did not provide. Things such as Zune and Xbox integration, a new browser and fully capable multi-touch functionality. It also removes things several major stuffs such as Smart Dialing (one of my favorite in WinMo), Copy Paste, Expanding Storage, Skinnable theme and many more. However, if you were to look at the user interface of WIndows Phone 7 Series, you can tell why Microsoft did not include the skinnable theme as a feature. Now we have several devices from venders like HTC, Samsung, LG and Dell etc are major player and Nokia will start soon.