XCode 8 Take a screenshot on a device
If you need a launch image for your app, you can use Xcode to launch an app on a device and capture a screenshot.
For iOS and tvOS apps, connect a device to your Mac before you begin.
For watchOS apps, connect an iPhone paired with an Apple Watch.
1、Take a screenshot using the Debug menu
Choose Debug > View Debugging > Take Screenshot of Active Device.
The new screenshot appears on the desktop.
Open the Devices window (choose Window > Devices).
In the left column, select your device, and in the detail pane, click the Take Screenshot button.
The new screenshot appears on the desktop.
When generating your app’s launch images, always capture images from devices with the appropriate screen size and resolution.
For a universal iOS app, this means capturing screenshots both from an iPad and from an iPhone or iPod touch.
If you are submitting your app to the App Store, capture all required screenshots that you upload later to iTunes Connect.
看巴懂的留言，这个估计都能看懂，留个便签，方便查询。
