Before revision:  These enable the aforementioned mixture of verifiability and privacy in a manner derived from public/private key pairs and digital signatures, generalised to avoid restrictive ownership of sensitive digital keys and/or data.
After revision:  Results: Our mobile phone app and distributed server architecture enable the mixture of verifiability and privacy in a manner derived from public/private key pairs and digital signatures, generalised to avoid restrictive ownership of sensitive digital keys and/or data.