We are testing game engines for our future games, there are many engines around and we obviously can't test them all so we assembled a list of requirements that would help us decide what is the right game engine for Pixibots.
1. Cross platform - we want to deploy the games on iPhone and Android devices easily.
2. Short development period - the engine must give us a lot of built in functionality, we want to focus on making the best game ever and not on loading textures, managing memory and such.
3. Support and documentation - there is nothing more frustrating than throwing away something that you worked on just because you're stuck with a critical bug and you can't get things to work.
4. Community - We want to work with an engine is used extensively, discussed by others and there is a live community of developers helping each other making professional games with the engine.
5. 3D support - although there are a lot of 2D games for mobile, we plan on moving to 3D games so even if it is not an immediate requirement we don't want to change the game engine later on and we prefer good support for 3D modeling.
6. Integration with other services - we need an easy integration with services such as: Google Analytics, Admob, Facebook, Twitter and others to maximize the game potential.
7. Physics - we need a built in physics engine or the ability to use common physics engines.
The game engines that we tested are: Unity, Corona, BatteryTech, Cocos2d, Marmalade, Shiva3D
In this list there are very different engines, some are low level platforms that you can built your engine on like Marmalade and BatteryTech, some are game design tools like Unity and Shiva3D.
We finally decided to go with Unity, we believe that Unity is the right engine for us because it fills most of our needs and it is the most suitable game engine for indie developers, Marmalade is also very impressive but it is intended for larger companies that have the time and resources to build their engine on top of a great platform.