Dydu chatbots are available on all devices: computers (via the Internet or a desktop app), tablets and mobiles (via the Internet or a mobile app).
Callbots are, by very definition, accessible by telephone (landline or mobile), via a phone number.
Voicebots can be accessed via connected objects that use voice, such as connected speakers, and can also be deployed as “voice chatbots”, to make them accessible for people with disabilities. They can be accessed in the same place as the chatbot (computer, tablet or mobile).