Apple introduced ReplayKit in iOS 9 for developers to add the ability to record gameplay in their apps. This seemed like it would be a popular feature when it was announced, but it has been underutilized by developers and widely ignored by gamers. You can see a list of games that utilize ReplayKit here. Each app is different, but most apps feature some kind of button that allows you to record your gameplay and even a commentary. Your videos are saved to your Camera Roll which allows you to easily upload them to your YouTube account by transferring them to your computer or by using the free YouTube iOS app.
How do I record my iPad gameplay and upload it to YouTube?
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