So, whether you need to keep a video that you're worried will disappear, or want to watch clips when you're away from cellular and Wi-Fi, here's how to download YouTube videos on an iPhone or iPad Author: Henry T. Casey. Downloading YouTube videos for offline use to watch later has always been a problematic endeavor. Dedicated third-party apps don't last long in the App Store, web-based converters aren't very functional on mobile, and rogue apps outside the App Store are tricky to sideload and open up the possibility of vulnerabilities. But that doesn't mean you still don't have a few good slicelive.com: Justin Meyers. Step 1: Connect an iOS device to your computer with a USB cable and click Trust on your iPhone to trust this slicelive.com run EaseUS MobiMover Free, go to Video Downloader, and tap the device icon to choose the device you want to download YouTube videos to, either your computer or iPhone/iPad.