SMSC number stands for Short Messaging Service Center Number. When a user sends any SMS, this SMS goes through a SMS service center before it is finally diverted to its destination. Think of SMS service centre as a gas station service stop on your way to your final destination. Since, SMS service centres are different for each service provider, service center number for each service provider will be different. If this number does not match with what you may see on the screen, one will have to contact customer/tech support to get the dialing sequence to set their SMSC number. One does not need the SMSC number set up to receive SMS. Without this SMSC number, one will not be able to send a single SMS!
You may refer to the following steps to set up your SMSC number for Chatr.
Step 1: Navigate to your messages on your Android.
Step 2: Use the Menu button on your phone to bring up message settings on your phone.
Step 3: Navigate to your SMS settings.
Step 4: Access your text message settings.
Step 5: Click on SMS service center option on this screen. Type in the SMS service center number for your network service provider.
Step 6: Once this number is set up correctly, you may proceed to send text messages.