Apple has updated iMovie for iOS to version 2.2.3. It allows you to start projects quickly by selecting multiple photos and videos.
You can also share to Facebook and Vimeo by using the standard iOS share interface. iMovie for iOS 2.2.3 also supports the Shared iPad feature in iOS 9.3 or later. Plus, it has stability and performance improvements.
iMovie for iOS 2.2.3 is available for free at the Apple App Store. It requires iOS 9.3 or higher.