When comparing Solar 2D (formerly Corona SDK) vs Modd.io, the Slant community recommends Solar 2D (formerly Corona SDK) for most people. In the question“What are the best 2D game engines?” Solar 2D (formerly Corona SDK) is ranked 15th while Modd.io is ranked 95th.
Ranked in these QuestionsQuestion Ranking
Pro Very simple to use
Corona SDK is completely free. That includes pro-tier plugins.
Pro Corona Simulator
Corona SDK ships with Corona Simulator, which runs your game/app directly on your PC/Mac and updates every time you make changes.
It provides immediate feedback to your actions, you can see your changes right on the screen, without necessity to make build to device. Getting instant feedback really boosts tenfold prototyping and development speed.
Pro Lua syntax
Uses the great and easy-to-learn Lua programming language.
Pro Good documentation and lots of tutorials
Pro Cross-platform desktop and mobile
Corona works on OS X, Windows and Android (including Kindle Fire & Nook).
Pro Very comprehensive API
It's very quick to get things up and running with Corona SDK. The API is extensive and while it's not 100% feature-complete with the iOS API, it's close enough that you could create tons of games and never run into a roadblock.
The API docs can be found here.
Pro Amazing learning curve
Corona does not throw photoshop-like madness full of buttons editor. You can go as fast as you want, learning and building game from ground up. Eventually, you'll learn how much corona is doing for you. But to start you don't have to master complex editor software. It's a great tool to learn to start game development if you want to learn how to program and make games. Your experience will be 100% transferable to any other Pro game engine.
Pro Content scaling
It's easy to create a game that looks good on many different sized mobile devices.
Pro Live builds - update builds running on a device automatically
With the live build feature, once you have created a build and installed on a device, you get lightning fast turnaround times because any change on the code or data is updated to the devices running the game (within the local WiFi) immediately. So changes can be tested on the real hardware within a very few seconds.
What's even more impressive, this even works flawless with multiple devices running the game. You have to use it to learn how good of a feature this is while development and even more, while doing QA. Imagine fixing bugs and everyone of your QA team/friends/whoever helps to get your game done, has all changes on his device without doing anything but waiting 5 seconds - outstanding.
Pro Marketplace for 3rd party plug-ins
Pro Great community
Pro Ability to call any native (C/C++/Obj-C/Java) library
Pro Completely free
Since Corona SDK became Solar2D, it's completely free, as only some third-party plugins are paid.
Pro Open Source
Since Corona SDK became Solar2D, it's completely open source under MIT license.
Pro Well supported
Pro Runs well on low-end devices
The game client doesn't use much CPU nor bandwidth.
By far, this engine is completely free to use.
Pro No installation required - super easy to get started
Modd.io runs in browser, it provides IDE, map editor, and asset manager all in one platform, so you don't need to download or setup anything.
Pro Easy to use free Asset Library
You can easily change your game assets (images, sound, etc) with a single click using modd.io Asset Library
Pro Has multiplayer support baked in
This engine supports up to 64 concurrent players, and hosts servers for you as well
Pro Perfect for Impatient game developers
It literally takes 5 minutes from signup to publishing my game
Pro Easy to use
Modd.io is designed for new/intermediate developers who wants to get into game development. You should be comfortable using the engine after spending about 15 minutes in watching tutorial videos
Con Closed source
Con Free, but not completely
Con Making a device build requires internet connection
To build your app for the device (iOS/Android/AppleTV) Corona requires to fetch resources from online. This would include base application template and plugins. This allows not to perform local build or use Xcode or Android Studio to do a build. Even Large games/apps would build very fast with good internet connection.
Your code never leaves computed. Corona SDK would transfer some information to determine which plugins and pieces has to be transferred in order to make a final steps in build.
As a bonus - you get basically one button press to get from your Corona Simulator game to game on a device.
Con The engine is evolving in a bad way
Over the last updates, many useful features have been removed, making it harder to create more complex games.
Con Not very secure
Modd.io comes with its own security issues. Many of them have been used to destroy eachother's games, which completely busts your progress on your game unless you have backed it up by exporting it's JSON.
Con Annoying asset size limit
Each asset is limited to 800kb (except for audio being 3mb) which is okay for simple assets but unacceptable for creating spritesheets for animations or tilesheets for the map.
Con Very flat map
No matter how well game maps are made, all of them look just not beautiful.
Con No/limited camera manipulation
You cannot create a shake effect which is also urgently needed in complex game creation.
Con Certain variable datatypes are urgently needed but do not exist.
Such datatypes as arrays composed of numbers, strings, etc are needed to create complex games but just do not exist in this game engine.
Con Joke-y community
Most of the staff team in the community are constantly behaving like jokers. It just always feels like 80% of the staff team is not the right pick for such a community.
Con The homepage is not good
The homepage allows players to join your game, but the way it works is just not good. The "unpopular 0 player" games get less exposure than the popular games. The tier system also puts a star on your game card which also lures players to your game making them think this game has a special event or something, giving a disadvantage to the less popular games which are still so called "Tier 1".
Con Not very powerful
This engine is ready to use right away, but already starts dropping framerate at over 1000 units which are not very active.
Con Tier-based servers with certain lockdowns
Modd.io "tiers" all the games you create. The very basic tier, commonly called "Tier 1" is very limited and removes motivation to develop a game.
Con You'll have to learn a new programming language
This engine has it's own IDE with a drag and drop style programming language. It does take a good 2 hours to get familiar with the API..
Con No lower level API access
You cannot access lower-level APIs through this engine, such as the renderer.
Con No single player support
All games in modd.io must support multi-player game mode.
Con Limited customizability
Modd.io is designed to be good at making "specific" kind of multiplayer games. Its strength unleashes if you don't care too much about the specifics in UI. For example, if you wanted to make a casual death match game, it is extremely easy to make it using modd.io. However, if you want to create a puzzle game with a unique UI, it becomes very time consuming.
Con No 3D support
This engine is limited to 2D only.