Cards and my mobile.

Simply remove the card in use from the wallet and use it independently thus eliminating any risk.

Thanks I was hoping I could just use my phone and not carry my cards around with me.

You can turn the NFC off in your phone settings, so your Google wallet won't work. I only turn mine on when I'm paying for something for fear of someone with a device to intercept the signal.
But, if you have more than one contactless card in your wallet, the machine can't differentiate between them.

A friend of mine did this and had her phone stolen along with her cards. Maybe not a good idea.

Thanks, given me food for thought.

If your Freedom pass is set as the default for contactless travel on TFL services, tapping your wallet with the pass should work just fine. Just make sure it's the one the reader picks up. Your debit card in Google Wallet shouldn't interfere with the Freedom pass transaction as long as it's not set as the primary payment method for travel.

Just an aside, a waiter on bringing our bill and the card reader, accidentally paid it himself with his phone which was in his pocket. If it hadn't happened to me l would have thought it was an urban myth.