The old post is not quite right then, C++ Integration works for all platforms.
You can for example use the available C++ Qt components to implement socket communication for networking.
Using native device features is also possible: (e.g. accessing the phone book on the device or telling the device to open the maps application)
For this it is required to implement the relevant code parts in the native programming language (objective-c on iOS or Java on Android) and call these functions from your C++ code.