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Corona is a cross-platform framework for creating apps and games for mobile and desktop. Create your project once and publish it to multiple types of devices, including iOS, Android, Amazon Fire, Mac Desktop, Windows Desktop, and even connected TVs such as Apple TV, Fire TV, and Android TV.
SpecsUpdate
Pros
Pro Live builds (Develop while testing directly on devices)
Instead of working in a simulator, then building and testing on devices, Corona lets you test directly on the device, whatever the platform. Or, indeed, test on all of them simultaneously.
Just build once onto each device, and then in the future any changes to your project are reflected immediately on the device or indeed devices.
Tweak your game and immediately see how it works on all your phones / tablets / Apple TV at once!
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 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.
Cons
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 Poor code editor
It uses Sublime with an add-on for Lua. Autocompletion ignores the context and pops up kinda template you have to edit. Debugging tools are also poor. It's like writing your application in Notepad++ instead of using a proper SDK like Visual Studio, Android Studio, etc. Moreover Corona is not free.
Recommendations
Comments
Out of Date Pros + Cons
Con Closed source
Since you don't have access to the code, you can't make changes to the SDK. You even have to implement workarounds on issues that have long been reported, but never fixed.