Sharp AQUOS Crystal - Manual (Page 425)

Settings 416
2. Touch an account > <account name>.
The account settings menu appears.
3. Select your account settings, and then update the settings you want to change.
The account options are updated.
Date & Time Settings
Use the Date & Time settings menu either to automatically use the network-provided date and time
or manually set these values, as well as select time and date format options.