Yes, you can! However, this is only for Android users.
If you are not connected to data/wifi, simply go to the app:
1. Click on the 'Me' tab.
2. Click on VIEW MY SAVED VOUCHERS.
3. Click on the voucher you want to redeem and you will be prompted to your voucher page. Click on SEND AN SMS TO REDEEM.
4. You will receive an SMS with the 4-digit redemption code.
5. Enter it on the page to redeem.
6. Your voucher is now redeemed successfully!