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The App Game Kit (AGK) is a piece of cross-platform games development software developed by The Game Creators (TGC).
SpecsUpdate
Pros
Pro Uses a powerful scripting language built for game development
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.
Pro Allows source to be compiled for Windows, OSX, iOS, Linux, Android, and HTML5
AGK allows you to write code that can be deployed to multiple platforms. This makes writing software for different markets very easy, as adapting the source to each platform does not require complex rework or branches.
There is also a free version for Raspberry Pi.
Pro Includes IAP, AdMob, and push with no extra setup
With AGK you can quickly set up In App Purchases for Google Play and the App Store with just a couple lines of code. AdMob comes setup so you only need just a couple lines of code to show ads. And push is 99% set up so you only need to register your accounts and update a couple lines of code. It's all very easy!
Pro You only need to to pay for the license only
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.
Pro Has support for multiple languages
AGK has two tiers, making the engine both friendly for beginners and powerful for more advanced users.
Tier 1 is simple to use, with a Basic-like language and its own IDE.
Tier 2 is a set of libraries with equivalent functionality that you can use with anything that supports the linker format. The most popular usage is Microsoft's Visual C++, along with Visual Studio as the IDE.
Pro Works extremely well for people who like a more programming-oriented approach to things
Super fast build times. Your projects will build almost instantly. This will allow you to do rapid iterations in development to test out additions and other modifications.
Pro Raspberry Pi free version available
A Raspberry Pi version is available and free. Users just need to register with the developer and then they can download.
Cons
Con No scene editor (yet)
In it's current state, App Game Kit is only a programming language - it doesn't have an editor. That means there's no way of adjusting your game other than changing your code, which can be time consuming.
There is one planned for development in 2017.
Con Very slow progress
There is very little progress going on with AGK. AGK is done by only 1 programmer and the progress indicates that this is a part time thing. Updates are few and far in between, and bug fixes sometimes take whole months to fix. The templates that come with the C++ libs do not work out of the box and need users to fix them!
Most integrated third party features, like Facebook & Advert commands use very old versions of the libs.
Con Few skilled developers and lots of bugs with very high turn-around on fixes
There are very few developers, even fewer who are working on AGK and not out marketing it as a working product, then out of those, few who seem to be skilled programmers.
There's no support for any type of sensors or GPS. The full API and even the compiler are riddled with bugs even at the time of this writing. For example the latest beta at the time of this writing, and years after initial release, you can corrupt compiles if you don't space function parameters just right, and HTTP calls simple don't function on some platforms. HTTP functions are early functionality.
Con Can almost only do trivial games
The editor is rather limited, not fully polished, and 3D is missing some key functionalities (3D is work in progress).
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Flagged Pros + Cons
Pro Broadcasting
Superb broadcasting function allows you to INSTANTLY see your app working on android or IOS.