Using Images Efficiently

When it comes to using images in our WatchKit app, the most important thing to keep in mind is performance. We want our images to appear quickly on the watch, and look good to boot. To that end, let’s look at various ways to get our images into our WatchKit extension and our watch app, and how to use different images for differently sized devices.

Using the Right Image Size

The two sizes of Apple Watch both sport Retina displays with an @2x image scale, but they differ in their point sizes. This means a full-screen image will be larger on the 42mm Apple Watch than on the 38mm. For some images this doesn’t matter; the image will remain the same size, and the content around it will have more room on the larger display. ...

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