I am a little confused. When I search the internet I see examples of Windows CE running on Raspberry Pi or Samsung ARM11. However, I cannot be sure if they hacked it somehow or CE officially runs on ARM devices.
If it does not, should I use Windows Embedded products to target arm processors?
And the last question is that How does Windows CE fare when compared to Windows Embedded 7 in terms of footprint?
Can anybody enlighten me please?
Yes, Windows CE (lately renamed Windows Embedded Compact) runs on ARM. Up to version 6 it supported also SH4 and in Compact 7 MIPS. Latest version is named (confusingly) Windows Embedded Compact 2013 and Microsoft is committed to support it up to 2023. It's a different kernel (real-time) but provides some compatibility at the API level with desktop and server versions. The new Windows IoT Core version runs on Raspberry Pi 2 (ARMv7) and uses the same kernel of the PC version.