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As you progress you'll unlock practice activities: free coding, predict the output, rearrange the lines, spot the error, tap to code, type checker, and more – all designed to get you reading and writing as much Swift as possible.  Completing lessons and activities also earns points and badges so you can monitor your progress as you go from zero to hero – it's the fastest and easiest way to learn Swift on the go.  It features 100 videos that walk you through the features of Swift in one minute or less, with each chapter backed up by a quiz to help make sure you understand before moving on.  diese App is an all-new app designed to make it easy and fun to learn Swift programming right on your iPhone.  Even better, diese App is free: no cost to download , and no surprise in-app purchases to unlock lessons. So what's stopping you? Dive in today!  Each day you can tackle a new daily challenge, pitting you against 10 random activities that will test your skills in a variety of areas.  Swift and the Swift logo are trademarks of Apple Inc.