What feature do you think every telemedicine app should have?

I'm researching telemedicine solutions and would love to hear real-world opinions from healthcare professionals, developers, and patients.

What do you think is the single most important feature in a telemedicine app?

Is it:

Seamless video consultations

Easy appointment scheduling

EHR/EMR integration

E-prescriptions

Secure messaging

A simple and intuitive user interface

Also, what's one thing you think most telemedicine apps still need to improve?