There are MANY phone and tablet apps for video.  Too many to keep track of! Major ones include:
–Lightt
–Vine
–Instagram now does videos

Videopad  I haven’t tried — “Video Editing Software Anyone Can Use: Designed to be intuitive, VideoPad is a fully featured video editing program for creating professional looking videos in minutes. Making movies has never been easier.” Free trial. 

Blurb Mobile  A mobile app from Blurb.iPhone or iPad only

Other software:

Soundslides  easy, cheap, not very powerful but pretty good – still images & audio.

iMovie – pretty easy, not very powerful

Windows Movie Maker?

Final Cut Pro X  NOT backward-compatible with earlier versions of Final Cut Pro.  Designed to be much easier to use than earlier versions — more like iMovie. Reviews are mixed.

Earlier Final Cut Pro is no longer available.  Powerful, steep learning curve.  People who have it are hanging onto it.

Adobe Premiere Pro   Powerful. Steep learning curve.