[Vinny]

Originally Posted by TC1

1. Microsoft makes an OEM version of their operating system available to the manufactures/OEMs, ie, HTC, Samsung, and others.
2. Various integrated circuit manufactures design cips that will support both operating system and the cell phone functions needed.
3. Manufacturers like HTC design a product using various sources of info, the two predominant ones being "reference designs" provided by Microsoft and the chip makers (Qualcomm, etc). It is up to the manufacturer to make the hardware and software work together, ie, specialized drivers. Who develops these drivers is variable, sometimes the chip makers make baseline ones available to be tweaked, sometimes the chip makers just make the hardware API spec sheet available and it's up to the manufacturer to write their own drivers.
4. The manufacturer will attempt to 'add value' by incorporating features in software, like the TouchFlo interface (developed in house by HTC) or incorporating a third-party innovations (like Samsung did with the Picsel browser). The idea here is to make a product that many of the carriers will want to carry in their product line.
5. The carrier will submit the OEM version of the product to the FCC for use acceptance on the U.S. airwaves.
6. The various carriers will buy the OEM version from the Manufacturer and then say "Ok, this what we want you to do to make it 'our' version." At a minimum this includes almost always the outer cosmetics, ie, the case, its colors and materials, silk screened logos, buttons, etc.
7. The final thing that is done is that the the carriers will develop some minor crapware of their own to generate additional revenue. One needs to keep in mind that this crapware just sits on top of the OS like any other 3rd party application, they are not redesigning the code of the OS or the drivers.

Isn't Windows Mobile based on Windows CE? I know on CE you can get the platform builder and select which parts of the OS you include or modify. I would assume if WM is based on CE the same would apply. If so, the manufacturer or Sprint, whoever is responsible for the ROM, would have more say in the ROM than Microsoft.