Cocos2d-x and Cocos Creator vs AppGameKit 2.0

25% of iPhone games are made using Cocos2d-x.

This means you will not be alone in development, and will have access to a large community. You'll know you are developing for an engine that works.

Documentation includes a programming guide, API reference, video tutorials and massive reference test code project showing all functions and giving working code to the user.

A new feature since Cocos2d-x v3.1 is support for 3D models (in your 2D game), not only this but support for skeleton animations is included too! This awesome feature allows for impressive characters in your game along with easier, more fluid and realistic animations.

It supports Lua and Javascript with full feature support.
Especially with Cocos2d-JS you can develop games cross web and native, and the native solution have great performance with JS Bindings, much better than hybrid solution.

Cocos2d-x forums are active.

Cocos2d-x is not only open source but also supported by Chukong Technologies of China and USA.

Regularly updated and adding support for the latest technologies. 2014 has already seen the release of Version 3, a new Cocos Studio development toolkit (optional) and support for new technologies like skeleton animation systems Spine and Adobe DragonBone.

Cocos2d-x is C++ based engine and it has CPU advantages for most platforms because of that. It uses polygonal mesh methods for sprite rendering for using GPU advantages. (You also use quad methods for benefit CPU).

Because it is based on Pyglet.

On top of supporting pretty much all existing platforms (except consoles), Cocos Creator (Cocos's IDE) allows you to write 1 code that runs on Android, iOS, Windows, MacOS and HTML5 (not Linux though).

Through the use of SDKBox you can easily integrate 3rd party SDKs and plugins for each version of Cocos2D (Lua, C++ or JavaScript), you just choose the SDKs to integrate and SDKBox will do the rest.

For example, if you want to add a rating plugin, you use sdkbox::PluginReview::init(); and if you want to add the Vundle Ad Network SDK, you use the one packaged in SDKBox SDKBOX sdkbox::PluginVungle::init();.

It has a built-in Python interpreter that allows for easy debugging.

Cocos Creator (Cocos' IDE) comes with scene editing, UI editor, animations & particle editors and whatnot. It's also easy to use and pretty intuitive if you read the official documentation & tutorials. Way way better than the old CocoStudio.

Hundreds of video tutorials available.

The AppGameKit Basic can now export to HTML5.

Supports developing games for Android, iOS, PC, Mac, Linux and now HTML5.

There is no charge for upgrades, or for extra platforms (the HTML5 version just appeared in the latest version), there are no subscription fees or other usage charges. If you publish onto either Apple or Google's stores you will have to pay their costs, of course, but the makers of AGK do not take a cut of this themselves.

Plug-ins can now be added to the Windows platform. Create your own Tier BASIC commands and call them using the AppGameKit Basic script language style.

AppGameKit supports instant testing on all connected devices. With the push of a button you can run your game on any device connected to the development machine.

Every function is fully documented with examples and exercises. The Tutorial PDF is a full Introduction to 3D game programming with integrated references to every functionality and its most important usecases. The documentation is regulary updated.

Program in tier 1 BASIC programming for every 3D game need.

A Raspberry Pi version is available and free. Users just need to register with the developer and then they can download.

It is a compilation based language, but the compilation is very fast. A project of about 1800 lines of code, for example, can compile almost instantly. (That's because it does not compile, it's an interpreter)

Informed, timely and intelligent feedback from the AGK forum.

There are plenty of functions which facilitate development and deployment. For example, the AGK player immediately plays the updated bytecode on Android devices then the online site helps with building an APK file for Google Play Store in minutes.

Software produced with the App Game Kit is written in a language called AGK Script. This language has powerful inbuild commands including commands for 2D graphics, physics and networking. The commands make use of the platforms' native functions to improve performance. They are also designed to enhance code readability. The AGK Script commands have extensive online documentation.

It runs fast with BASIC but if you want more you can use C++, it's also easy to use.

Libraries which provide the same functionality are available for the five platforms, so you can code in C++

AGK comes with an Integrated Development Environment (IDE) based on the Code::Blocks IDE for writing AGK scripts. A key feature of the IDE is its ability to broadcast compiled programs to other devices for testing.