Callio is not a diversion based telephone system. Callio utilises a sip trunk service that makes it more secure than VoIP systems because calls bypass the public internet and instead use private data connections which decreases the likelihood of any breaches.

Unlike other services that provide customers with a local land line number which diverts inmate calls to a user’s mobile phone, Callio allocates users with their own personal land line number which is registered to their name and operated from the Callio app installed on their mobile phone.

This allows calls made by inmates to the local land line number to come through directly to the users mobile phone. It is this unique feature and unique system which allows Callio to offer users and inmates the cheapest telephone service available because it cuts out the additional costs of diverting the call to a mobile phone number.