[emptybits]

Disable your locked phone from always listening for "OK Google" or "Hey Siri". Protected, no? Their list of five ways to "defend against SurfingAttack" doesn't include this obvious one. i.e. If you want to give a voice command, pick up your phone and press a button to speak. Protected and still pretty darn convenient IMO.

Otherwise, great project and succinct video proof of how clever conveniences often conflict with security.

[seiters]

Thanks for the comment. This defense works: but you have to remember to lock your phone when you put it down.

[ThePowerOfFuet]

Siri can be used for many things when the device is locked.