What do you think of when you hear a phrase like “mental health chatbot” or “virtual therapy assistant”? Do you imagine a glitchy interface, robotic questions and a sterile textbox format in which to document your most private thoughts and feelings? Perhaps you picture an easy, cheap way to keep on top of your mental well-being; something less intimidating than starting therapy with a person. It’s possible your mind turns immediately to privacy and data leaks. Or maybe you think simply of an app you’re already using. 

It’s hard to quantify exactly how many people use mental wellness apps, partly because there are so many different options available. According to the American Psychiatric Association, there are around 20,000 such apps on the market. But the
number of subs...