Method 1
1. Press "Edit" button in main screen.
2. After pressing "Edit", following screen appears.
3. "Delete" button appears after pressing

4. You can also delete a folder by same operation as step3. If the folder have any item, a dialog appears as below. If you have no problem, press "OK" to delete the folder.
5. Edit mode ends by pressing "Done" button on top-right corner.
Method 2
Slide you finger to left or right on a account you want to delete. Then a "Delete" button appears. You can delete the account like method 1. You can cancel by pressing blank space.