Which game engine should I use?

Disclaimer: This is not an exhaustive list, nor does it get into all the nuances of the ones mentioned.

• ImpactJS
• MonoGame
• Unity
• Phaser
• PhoneGap

ImpactJS

ImpactJS.com

JS game engine using Canvas.

Pros

• Easy collaboration
• Nice level editor
• Easy deployment to:
• Web
• Additional deployment with Cocoon JS (or other service) to:
• Apple AppStore (iOS)
• Google PlayStore (Android)
• Amazon AppStore (Android)
• Ouya (Android)
• Chrome Web Store
• Pokki

Cons

• Commercial (Although I already have a license)
• Reliant on 3rd party services for deployment options
• Is best used for limited game styles/types.
• Performance limitations
• Possible platform limitations
• No 3D

MonoGame

MonoGame.net

Pros

• Relatively easy collaboration
• Free
• Open Source
• Deploys to:
• Windows
• Mac
• Linux
• Additional deployment with Xamarin to:
• iOS
• Android

Cons

• Additional deployment with Xamarin costs money
• Xamarin Store
• $300 /dev/platform/year for indie license
• $1,000 /dev/platform/year for business license
• $1,900 /dev/platform/year for enterprise license
• Best suited for 2D games, 3D part is relatively new

Unity

unity3d.com

Pros

• Graphical level/world editor
• Free (with limitations)
• Deploys to:
• Everywhere

Cons

• Commercial, pay for additional features (and platforms?)
• Unity Store
• Subscription model starts at $75 /month/dev
• $1,500 for pro version
• Additional $1,500 for each mobile platform
• Additional $500 for Team License
• Collaboration issues? (I've heard from multiple sources that collaboration can be painful with Unity)

Phaser

Phaser on GitHub

Newer open source JS game engine using Canvas. Created by well known HTML5/JS dev (Photo Storm).

Pros

• Open Source
• Easy collaboration
• Easy deployment to:
• Web
• Additional deployment with Cocoon JS to:
• Apple AppStore (iOS)
• Google PlayStore (Android)
• Amazon AppStore (Android)
• Ouya (Android)
• Chrome Web Store
• Pokki

Cons

• Very new, unproven
• Is best used for limited game styles/types.
• Performance limitations
• Possible platform limitations
• No 3D

PhoneGap

phonegap.com
build.phonegap.com

Mobile development using HTML and JS, along with a compilation step or use of the PhoneGap Build service (currently free). Not really a game engine, but could be used for menu driven games (Word games, choose your own adventure, stats, etc.).

Pros

• Easy collaboration
• Web Development skills transfer
• Free for now
• Deployment to:
• iOS
• Android
• Windows Phone
• Blackberry
• HP Web OS
• Symbian

Cons

• Not really a game engine
• Free for now
• Reliant on 3rd party services for deployment options