Is there a way to take a screenshot gif (screenvideo) of an iPhone interaction? I'd like to take a motion-recording of an interaction on an iOS device while it's plugged into a computer. (To report a bug or demonstrate a feature, without making a shakycam video with another device, i.e. my friggin' iPad )

Does Xcode or a similar tool support this?
If you use a Mac, you can connect your device to the computer and use Quicktime to capture the screen as a video. After selecting 'New Movie Recording' your device will be offered as a source.

https://www.tekrevue.com/tip/record-iphone-screen-quicktime/