C++ support on embedded devices and smartphones is kind of iffy. First there might be actual language features missing because of a simplified runtime system those systems use. I'm primarily talking about exception handling but also other features.

Second is the standard library. The systems in question might not ship with a decent C++ standard library ("STL").

Third problem is C++0x. If I were to write C++, I would definately want to use C++0x, the language has cool features like auto and lambda and the standard library has nice additions w.r.t. C++98, especially std::thread and std::chrono.

Third is the API's you have to deal with. Using C API's in C++ apps either requires you to use a wrapper layer or give up using constructors, destructors, exceptions or at least give very special attention to those and end up writing code with a bastardized C/C++ hybrid.

Don't get me wrong, I like C++ but it's always a PITA to try to write something portable with it.