IOS 12 will feature a very useful Shortcuts tool.
Shortcuts is an analogue of Automator on macOs, ie the ability to combine several actions into one. Many processes will be available in Shortcuts, for example, to download videos from social networks or YouTube you do not need to install special applications, it will be enough to start the process in Shortcuts. It is also possible to quickly transfer from one format to another and many more interesting processes. By the way, processes for Shortcuts can be written in Java Script!