Apps moved near the top of the list will take priority in the row of apps in your Share Sheet. Under Suggestions, you can add/remove an app from the Share Sheet by toggling the switch next to it.

With better app sharing a staple of iOS 8, organization is going to be crucial in making the experience pleasant.

It's free, every week, in your inbox. Sign up now! Anyway, Apple’s new share sheets in iOS 6 could end up getting populated by icons from other apps soon enough.