OneShot is a new app for iPhone that lets you highlight and share your screenshots. Meant to help you share articles, OneShot lets you highlight your favorite passages, customizing how your selections will look when you share them.
OneShot auto-detects screenshots taken on your iPhone. Select the screenshot you want, then get to editing. You can crop the image down to your favorite section, and highlight particular passages. You can choose your background color by sliding your finger over the color pad.
Finally, you can select the source that should be detected from your image. Then you can share your final image on Twitter or save it to your Camera Roll. OneShot is available on the App Store right now.