The difference between your app's Base SDK and Deployment Target

[kjmcneish]

Your app's Base SDK specifies the highest version of iOS that your app supports. When your app runs on a device that is running your app's Base SDK, it runs the full feature set available in your app. The Base SDK should usually be set to "Latest iOS".

Your app's Deployment Target specifies the minimum version of iOS that your app supports. So, your app's Deployment Target should always be set less than or equal to its Base SDK.

If your project has multiple targets, you can set the Base SDK at the project level and the setting is inherited by all targets. You can also change the Base SDK for a particular target at the target level.

All the best!
Kevin McNeish
Author of Learn to Code in Swift: https://itunes.apple.com/us/book/learn-to-code-in-swift/id942956811?mt=11
Check out our Robot Tic-Tac-Toe app: https://itunes.apple.com/us/app/robot-tic-tac-toe/id990638517?mt=8