This app does one thing and one thing only - mark all your SMS as read. No more frustration opening each and every unread message to mark it read - this app does it in one click.
You can either launch the app and touch the check mark or you could add a shortcut to your home screen.
Note to KitKat users:
In KitKat and above, the application should be the default messaging application for modifying read status of SMS. So, for KitKat and above, app will ask to set 'Mark All SMS Read' as the default messaging app. Once all SMS are marked read, the app will ask to change back to the original messaging app. So, for KitKat, it will be 3 clicks.