Solar2D

Overview

Solar2D is a free, open-source 2D game engine that uses Lua. It suits developers making games or apps for mobile, desktop and connected TV, especially when rapid iteration matters. Its broad target list and native-library access are useful strengths, but projects must be built around Lua.

Key features

The Simulator displays code changes immediately, and deployed apps can receive code and asset updates over a local network. This shortens the feedback loop for refining a project across devices; it is a practical advantage for frequent iteration, rather than a substitute for a different language or engine.

Plugins can add advertising, analytics and media features, with options in a free directory and third-party stores. For integrations beyond plugins, Solar2D Native can call C, C++, Objective-C and Java libraries or APIs. That extends what Lua projects can connect to, though platform-specific work may require native-code skills.

The documentation includes guides, tutorials, an API reference and plugin material, while forums and Discord provide community discussion and support. The project is community-maintained, with Vlad Shcherban as principal developer.

Pricing

Both the Free and Solar2D plans cost nothing. The maker says there are no engine fees, charges or royalties for indie developers or large publishers, so there is no paid tier to unlock a different set of engine capabilities. There is no free trial; the engine itself is free to use.

The source code and resources are available under the MIT license. The maker also says Solar2D does not track app users or gather anonymized data, and that games make only the network requests their developers specify.

Platforms

Solar2D lists iOS, tvOS, Android, Android TV, macOS, Windows, Linux and HTML5 as targets. Its platform range makes it relevant to developers planning for phones, computers and connected TVs from one codebase. The maker also describes mobile export, multiplayer tools and development for mobile, desktop and connected TV.

Who it's for

Solar2D is a strong fit for developers comfortable with Lua who want a no-royalty 2D engine, quick iteration and access to a wide set of listed targets. It can also suit teams that need plugins or expect to reach native libraries through C, C++, Objective-C or Java. Look elsewhere if your project depends on a scripting language other than Lua.

Pros and cons

• Pro: The engine has no fees, charges or royalties, making its cost straightforward for both indie developers and large publishers.
• Pro: Immediate Simulator updates and local-network delivery of code and asset changes support a fast iteration cycle.
• Pro: Plugins and native-library access provide routes to additional features and platform APIs.
• Con: Lua is the scripting language, so teams committed to another language will need a different fit.
• Con: Native integrations may involve platform-specific code in C, C++, Objective-C or Java.

Alternatives

Godot Engine is another free, open-source game engine and may suit developers comparing no-cost engines without royalties or contracts.

Defold is worth considering for a free engine with no licensing, runtime or royalty fees and targets including extension support.

Codename One may fit developers who prefer a freemium tool with a free plan that includes 100 cloud build credits monthly, subject to per-build credit costs and a user JAR limit.

Felgo is an alternative with a free Personal plan for annual turnover under €50k and a Startup plan priced at €79 a month, billed annually.

B4X may suit Android developers seeking a free B4A plan for Android development, including commercial use.

DroidScript offers a free download with optional paid plugins and donations.

Monaca may suit teams wanting a free cloud IDE, debugging tool and limited project and remote-build allowances.

Qt Creator offers an open-source version, with Qt framework use subject to LGPL or GPL obligations.

Browse Game Engine Software or Mobile Development IDEs to compare more tools.

Verdict

Choose Solar2D for Lua-based 2D game or app development when free use, fast iteration and a wide target range are priorities. Its clearest reason to look elsewhere is equally direct: a project that requires a scripting language other than Lua needs a different engine.