What are some alternatives?
When comparing MonoGame and AppGameKit, you can also consider the following products
RPG Maker - Make your own PC game with RPG Maker. Our easy to use tools are simple enough for a child, and powerful enough for a developer. Try it free today!
Orx - Orx - a portable open source game engine
Corona SDK - Cross-platform mobile app development.
Unreal Engine - Unreal Engine 4 is a suite of integrated tools for game developers to design and build games, simulations, and visualizations.
ct.js - ct.js is a 2D game editor (desktop app) based on web technologies.
GDevelop - GDevelop is an open-source game making software designed to be used by everyone.