That turned out not to be quite as true as they said it was...<p>&gt; While the WWDC app does in fact use Swift, it’s not as much as you might think. Out of 281 classes, only 6 are written in Swift. The Apple Store app is also using Swift for its watch app. That’s about all the production Swift I could find from Apple on iOS.<p>Source: <a href="https:&#x2F;&#x2F;medium.com&#x2F;@ryanolsonk&#x2F;is-apple-using-swift-4a6c80f74599#.l37exis2p" rel="nofollow">https:&#x2F;&#x2F;medium.com&#x2F;@ryanolsonk&#x2F;is-apple-using-swift-4a6c80f7...</a>