Secret codes of iPhone

-*3001#12345#* and tap Call - Enter Field Mode
- *#06# - Displays your IMEI
 - *777# and tap Call
 - Account balance for prepaid iPhone
- *225# and tap Call
- Bill Balance (Postpaid only)
 - *646# and tap Call
 - Check minutes (Postpaid only)
 - *#21# and tap Call
 - Setting interrogation for call forwards
 - *#30# and tap Call
 - Calling line presentation check
- *#43# and tap Call
- Determine if call waiting is enabled
 - *#61# and tap Call
 - Check the number for unanswered calls
- *#33# and tap Call
- Check for call control bars
- *#76# and tap Call
- Check whether the connected line presentation is enabled or not
- *#62# and tap Call
 - Check the number for call forwarding if no service is available
- *#67# and tap Call
- Check the number for call forwarding when the iPhone is busy
 - *3282# and tap Call
– See your data usage
 - *#31# and tap Call
 – Outgoing caller ID
- *729 and tap Call
– Make a payment - *67 and tap Call
- Block caller ID