JUCE is an open-source cross-platform C++ application framework
Blynk library for embedded hardware
Cross-platform, cross-blockchain wallet library
Insanely fast native C++, Swift or Kotlin modules
Vulkan & C++17 based Scene Graph Project
LÖVE is an awesome 2D game framework for Lua
OpenGL ES to Metal API translation layer
Lua API wrapper with advanced features and top notch performance
Hook Framework for Android/IOS/Linux/MacOS
Node.js virtual machine for Android and iOS
A small, portable and extensible C++ 3D coding framework
Realtime 3D engine for game development
A fast JSON parser/generator for C++ with both SAX/DOM style API
How to build ROS (Robot Operating System) for the iOS platform.
A cross-platform OpenGL based lightweight scenegraph library