Just FYI...
For Starhub prepaid users, if your main balance falls below $0.22, you can activate 'Happy Xtra':
http://www.starhub.com/personal/support/mobile/value-added-service/prepaid/happy-xtra.html
'Happy Xtra' is one of the Starhub prepaid VAS:
http://www.starhub.com/personal/mobile/prepaid-plans/value-added-services.html
Once you successfully activated 'Happy Xtra', you'll get FREE 2 mins local outgoing call time & 10 FREE local outgoing SMS.
This may be useful to those who do not subscribe to any data plan & Starhub prepaid main balance happens to fall below $0.22 -- and thus becomes UNCONTACTABLE (until the Starhub prepaid is topup again).
To activate 'Happy Xtra', use the USSD code: *123*6*2#
Whenever you top up $10 (or more) to your Starhub prepaid, you're entitled to activate 'Happy Xtra' -- when needed.
But you cannot actually activate 'Happy Xtra' UNTIL your Starhub prepaid main balance falls below $0.22.
The FREE 2 mins local outgoing call time & 10 FREE local outgoing SMS given -- after activating 'Happy Xtra' -- will be valid for 3 days.
After 3 days, the FREE minutes and SMS will expire and any unused 'Happy Xtra' balances will be forfeited.
Each time your Starhub prepaid main balance falls below $0.22, 'Happy Xtra' is not automatically activated, you'll have to activate it manually.
I know, I know, there are people who use Starhub prepaid for years & not aware about this 'Happy Xtra' feature/VAS