IOS 12 is not a major upgrade but there are useful some new features, released Sept 2018
Control Centre and the Switcher
Instead of calling up these two together, you now find the Control Centre on the iPad by swiping down from the right top of the screen. On the iphone, swipe up from the bottom.
Get the Switcher (displaying all the open apps) by swiping up from the bottom frame and hold you finger for a second or two. A short swipe will open up the Dock. Also double clicking the Home button will open the switcher.
Both of these gestures are getting ready for the Home button to disappear from iPads, as on the iPhone X.
This new tool in Settings records what you have been using your iPad or iPhone for in the last day, or week. You can keep track of your usage this way. You can also set limits on your time on a particular app, or control and monitor children’s time on apps.
Keyboard turns into a track-pad
A useful little trick whenever you are using the screen keyboard: hold you finger on the space bar for a second and it goes blank. Then slide your finger, and the cursor follows you finger movements, just like a track-pad, allowing very quick editing of spelling errors and so on. It is quicker and easier than placing a finger on the text to get the cursor to appear.
Voice Memos is now on the iPad and provides a very quick way to record voice messages. These can be synced to iCloud, providing easy access between devices. Voice Memos can be sent by email or messages. Easier than typing?