Your work in the editor will automatically save a draft to your device periodically while you are working. This makes it easy to update a page without stressing over how it looks on the web until you are ready to publish! Pages will show when they are still in draft mode and have not been published. 

Tap Edit to start right where you left off. When you are ready to publish just tap Publish.

If you don't want your most recent edits saved, check out this article!