There are several popular tools and engines used for mobile game development, each with its own strengths. Here are some of the top ones:

Unity: A versatile engine that supports both 2D and 3D game development. It’s known for its user-friendly interface, extensive asset store, and strong community support. Unity is widely used for mobile games on both iOS and Android.

Unreal Engine: Known for its high-quality graphics and robust features, Unreal Engine is a great choice for developers aiming for AAA-quality games. It supports both 2D and 3D games and has a visual scripting system called Blueprints, which is useful for those who prefer not to code.

Godot Engine: An open-source engine that’s gaining popularity due to its flexibility and ease of use. It supports both 2D and 3D game development and has its own scripting language, GDScript, though it also supports C#.

Cocos2d-x: An open-source framework for building 2D games. It’s lightweight and suitable for developers who want a more hands-on approach to coding.

Buildbox: Known for its drag-and-drop interface, Buildbox is geared towards those who want to create games without needing to code. It’s user-friendly and designed for rapid prototyping and development.

GameMaker Studio: A versatile tool for 2D game development with a user-friendly interface and scripting language called GameMaker Language (GML). It’s popular for indie games and smaller projects.
CryEngine: Offers high-quality graphics and is used for both 2D and 3D games. It’s known for its powerful features and realistic visuals.

Corona SDK: A framework for 2D game development that’s easy to use and provides cross-platform support. It’s known for its quick development cycle and Lua scripting.

These mobile game development tools vary in complexity and capabilities, so the best choice depends on your specific needs, such as the type of game you’re developing and your level of experience.