to commonly asked questions.

How can I free up space on my iPad?

Remind me again how to free up storage space. We have done this before but I don’t have a clue. 1st generation Pro.

You can go into Settings/General/iPad Storage.

Once there, you'll see a list of all the categories taking up space on your iPad.
Often it's Podcasts, Photos, Audiobooks, Messages, etc…

Depending on what you see there, the next steps vary. You can choose to only optimize your photos library if that's taking up space,

You can choose to remove movies you may have stored locally.

You could tell your iPad to only save the last 30 days of text messages if that's the issue.

So overall, there's no one button to just recover space. It all depends on what's taking up the space in the first place.
This image is a theme.plist hack