How can I develop mobile apps with C++?

The beauty of C++ is that it is a general purpose programming language. This makes it a fit for any platform. Just know your tools well and choose what fits your project.

Usually C++ is used for developing machine learning, image, audio, speech, language processing core libraries that you may connect to on a native mobile application using a wrapper.

In Android for example, one would use NDK to call C++ libraries.

Using C and C++ Code in an Android App with the NDK

Android NDK beginner's guide : discover the native side of Android and inject the power of C/C++ in your applications

On iOS, you may use C++ binaries directly in your project. Another approach is to link to headers written in C++ in your code, but I read it should be done with caution to avoid performance penalties.

Using C and C++ in an iOS App with Objective-C++

http://www.drdobbs.com/cpp/interoperating-between-c-and-objective-c/

Mixing Objective-C, C++ and Objective-C++: an Updated Summary

http://www.drdobbs.com/cpp/problems-when-linking-objective-c-and-c

Cacoa & Cacoa Touch are a native API for Mac OS and iOS that could also help in coordinating interaction between your C++ & iOS mobile code whether it is in objective C++ or Swift.

Using OS X Native Application Environments

Using Swift with Cocoa and Objective-C (Swift 3.0.1): Basic Setup

App Development for Mac and iOS

http://www.skilledup.com/article...

However, for the new Swift iOS development, you will have to use a wrapper again just like with Android.

Using C ++ code and libraries in applications written in Swift

Some libraries have a framework for iOS such as OpenCV - a main library for computer vision - and in such a case you may not need use C++.

Linking OpenCV to an iOS project

OpenCV Tutorial: Real-time Object Detection Using MSER in iOS

You don’t seem to have trouble developing Windows Phone applications in C++, since Microsoft takes care of such.

Getting started developing apps for Windows Phone 8 and Windows 8

Create a Hello World app in C++ (Windows 10)

A similar arguments holds for generic Symbian platforms:

Getting Started

Step by step tutorial for your first Symbian Application

Microsoft takes it even further and allows you to develop Cross Platformmobile applications using Visual C++

https://msdn.microsoft.com/en-us...

This approach is similar to Qt Framework in C++

Qt - Mobile App Development

You may also consider CX a dialect of C++ for Windows Apps development

Component Extensions - A Tour of C++/CX

As a bonus you may give a try to Cider library in C++

Gallery :: Cinder

Having that many tools at hand you may pick the right one depending on what you’re trying to achieve since this is a generic question. The project at hand dictates the right approach.

C++ is a smart language for smart people