You don’t want to edit your experiment after launching it, as this will pause your results rolling in. Luckily, you can easily adjust your Audience Targeting in the Results section. No need to return to the editor.
In the Results section, click on “Settings” in the upper right corner. The “Options” menu will now pop-up.
In the Audience tab, you can change the device targeting, and more if your click “Advanced options”.
When you’re done, click “Save and close” to save any changes.