Sounds to me like his bank is the Commonwealth Bank of Australia(1), so Google Wallet is a non-starter. Coin is interesting, but the payments landscape in .au is rapidly moving away from card swipes to Paywave/Paypass. I've seen quite a few places that offer Cash or Tap, no swipe (I presume because of the fee structure).
Commonwealth Bank charge $2.99 a year regardless of what you want to do. To use their Android app, they also bill you that to have the functionality turned on.
The annual fee is not applicable in case of the PayTag (https://www.commbank.com.au/personal/can/can-tap.html). Also, can you refer me to the doc that mentions the extra cost of using the Android app for that purpose?
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