The first time you take a screenshot after updating to iOS 11, you're in for a surprise.
The process hasn't changed. You still press the power and home button at the same time, which is followed by a screen flash. However, on the new OS, you'll see a thumbnail of the screenshot placed in the lower left corner of the screen.
Take another screenshot and another thumbnail is stacked on top of the previous screenshot, and so on. There's more to it than that, so let's take a look.
Tap a screenshot thumbnail to open a dedicated screenshot editor with tools that let you crop, draw, write, add a signature or highlight areas of the screenshot.
Once you're done editing the screenshot, you can share it directly from within the tool. After sharing, tap on Done; you are then asked if you want to delete the screenshot(s) (Finally!) or save to the Photos app.
If you'd rather wait or skip the edit tool for a screenshot, you have two options: Ignore the thumbnail until it disappears, or swipe it off the screen.
The screenshot(s) will automatically be saved to your camera roll where you can then edit the screenshot using the Markup tool.