The latest version of the TCB app now has a Groceries section. This brings up a list of offers which are powered by Shopitize, so the same functionality. Select the offer, snap the receipt and (hopefully) straight in the account. From what I can see the offers are not the same as those currently listed on the normal Shopitize app this week, but are for items that have been there before (like Original Source shower gel and Heinz Ketchup).

I can't comment on the immediate add to the balance bit as yet as I haven't selected an offer, but will report back if no-one else does in the meantime. It can't be any worse than the CheckOutSmart offer delays...!

This functionality is confirmed on the Android version of the app, not sure about iOS.