Sharp AQUOS Crystal - Manual (Page 203)

Messaging and Internet 194
Text and MMS Options
The messages settings menu lets you control options for your text and MMS messages including
message limits, size settings, and notifications.
1. From home, touch > Messaging .
2. On the Messaging screen, touch > Settings. You can set the following:
n
SMS Enabled: Set up an application used for sending and receiving SMS.