How to get Videos on iPhone?

So I deleted some of my apps a while back to make space for something, and I think one of them might have been the starter app "videos". I tried looking it up in the app store but it's not there. I need it to transfer a downloaded video from my computer to my phone. Thanks. (BTW, if you know of an efficient way to transfer videos from computer to iPhone let me know.)

Videos by Apple
https://appsto.re/gb/-Vzdcb.i

ITunes is the best way to transfer videos to and from an iDevice