Please don't forget to update your study data before logging out!
1. Pull down Home screen to update your study data.
2. Tap the button with some short lines on the top left of "Home."
3. Tap "Log out."
4. Tap "OK" for the message that mentioned all unsynched data will be lost. (This message shows up every time you attempt to log out. Since you update the data on step 1, there is no unsynched data)
5. In the blue screen, tap "Sign in" at the bottom.
6. In the Sing in screen, enter your registered email address and password.