Apps similar to GDevelop include Godot Engine, which is free and open source. Other options are Unity, Scratch, Wick Editor and LÖVE. There's no shortage of Game Development Tools like GDevelop, with more than 100 alternatives for Windows, Linux, Mac, the web and Android.
Stride (formerly Xenko) is an open-source C# game engine designed for the future of gaming. It comes with a full toolchain and is especially well suited to create realistic games but allows you much more!.
Japan
Scirra Construct is a 2D game development engine with a focus on building games visually. No programming is required though the software uses a visual method for event handling that relies on programming concepts like variables, loops and conditions.
United Kingdom
A extremely powerful application to make games in python as well as in visual programming
Redot Engine is a feature-packed, cross-platform fork of the Godot game engine to create 2D and 3D games from a unified interface. It provides a comprehensive set of common tools, so that users can focus on making games without having to reinvent the wheel.
ct.js is a 2D game editor (desktop app) based on web technologies. It aims to be an extensible yet simple game-making tool, accessible for both newbies and experienced game developers.
Russia
Browser-based 2D game creation engine using a visual event-driven system, integrates JavaScript for advanced development, requires no installation or prior programming, supports exporting to HTML5, mobile platforms, Xbox One, and enables real-time editing on any device.
United Kingdom
Suite for building 2D top-down role-playing games with detailed map, tile, and sprite editors, traditional turn-based mechanics, dialog and encounter tools, custom scripting, asset support, and publishing options, suitable for both beginners and advanced users.
Japan
Fibbo is a free and open-source web-based game engine that allows you to create interactive experiences using JavaScript, right in your browser.
Open 3D Engine (O3DE) is an Apache 2.0-licensed multi-platform 3D engine that enables developers and content creators to build AAA games, cinema-quality 3D worlds, and high-fidelity simulations without any fees or commercial obligations.
United States
cocos2d-x is a cross platform open source free 2D game engine for mobile gamedev, that is fast and stable, easy to learn and use.
Phaser is a fun, free and fast 2D game framework for making HTML5 games for desktop and mobile web browsers, supporting Canvas and WebGL rendering.
United Kingdom
RPG Paper Maker is a free game maker engine including a 3D universe with many 2D sprites and some simplified 3D objects. Pretty close to the RPG Maker series, RPG Paper Maker finally give a way to create RPGs in a totally 3D universe as easy as it is in 2D!
