Although I agree with most of the comments you said, I have to strongly disagree with "First class C++ support of Windows Mobile" when compared to iOS (or even Android). I have an entire non trial stack of C/C++ libraries that I use which I easily bring to Android and iOS using a cross-compiling build system we wrote (https://github.com/amigocloud/amigomake). The C/C++ dependencies include :
Freetype v. 2.4.10,
OpenSSL v. 1.0.1m,
Bzip v. 1.0.6,
libidn v. 1.24,
GEOS v. 3.4.2,
CURL v. 7.39.0,
Proj4 v. 4.8.0,
SQLite v. 3080700,
Jpeg v. 8d,
PNG v. 1.2.50,
Minizip v. 11.
uuid,
libwebsockets,
rapidjson,
Spatialite,
Coffeecatch,
tinydir,
Freetype-GL,
libtess2,
RTree,
Spline,
SHA,
lodePNG.
Getting this libraries to work on *nix platforms (e.g. Android or iOS) is easy. Getting them to work on Windows Mobile is a nightmare - starting with the fact that they don't even support things like OpenGL...
Those C and C++ dependencies are using OS specific APIs.
The developers not caring about writing portable code doesn't make it less first class on Windows Phone.
I don't see any chapter on ANSI C or ANSI C++ standards about OpenGL.
When I learned C and C++, targeting UNIX only didn't meant much, because POSIX wasn't the same thing across all UNIX systems and Windows wasn't the only non-POSIX OS.
So we learned to abstract the OS APIs properly.
Nowadays it seems we are reaching a UNIX mono-culture.
I have been developing code for 20 years using C/C++ - it sounds like you have been doing this even longer.
I think it is completely unfair that you simply dismiss and blame the libraries "because the developers did not care and wrote it without portability in mind".
I am not sure what your own personal definition of "first class citizen" is, but as such, IMHO it doesnt even make sense to argue it.
All I can tell you is that I can take all these projects and create a Windows 7 build that works - so the work to make it "portable" is there (even with all the nonsense of making sure they are compiled against the exact multithreaded vc runtime version and other windows quirks). MS has specifically chosen to not support other subsystems (e.g. OpenGL) that make portability easy/realistically feasible. To me, having a "hello world" work doesnt make a platform a "first class" system - bringing complex well known libraries and make them work does. That makes a first class citizen. I know we disagree - so we'll just have to agree to disagree :)
Freetype v. 2.4.10, OpenSSL v. 1.0.1m, Bzip v. 1.0.6, libidn v. 1.24, GEOS v. 3.4.2, CURL v. 7.39.0, Proj4 v. 4.8.0, SQLite v. 3080700, Jpeg v. 8d, PNG v. 1.2.50, Minizip v. 11. uuid, libwebsockets, rapidjson, Spatialite, Coffeecatch, tinydir, Freetype-GL, libtess2, RTree, Spline, SHA, lodePNG.
and are used by this cross-platform mobile app: https://github.com/amigocloud/amigoclient
Getting this libraries to work on *nix platforms (e.g. Android or iOS) is easy. Getting them to work on Windows Mobile is a nightmare - starting with the fact that they don't even support things like OpenGL...