According to the Lancet, a medical journal, the incidence of depression and anxiety has soared in the pandemic—by more than 25% globally in 2020. That, combined with more people using online services, has led to a boom in mental-health apps. But are they safe and effective?

Now that big companies prioritize employees’ mental health, some apps work with them to help entire workforces. But in a rush to develop some apps, there are dangers.

In October 2020, hackers who had breached Vastaamo, a famous Finnish startup, began blackmailing its users. … Threatening to share details of extramarital affairs and, in some cases, thoughts about pedophilia, the hackers reportedly demanded bitcoin ransoms from some 30,000 patients on the dark web. Vastaamo has filed for bankruptcy but left many Finns wary of telling doctors personal details, says Joni Siikavirta, a lawyer representing the company’s patients.

And then there are the pesky privacy issues.

“When I first joined BetterHelp, I started to see targeted ads with words that I had used on the app to describe my personal experiences,” reports one user. BetterHelp says it shares with marketing partners only device identifiers associated with “generic event names,” only for measurement and optimization, and only if users agree. The product is marketed as clinically validated based on a scientific study that concluded that humans could form meaningful bonds with bots. Of its ten peer-reviewed reports to date, says Woebot, eight feature partnerships with the principal investigator with no financial ties to it.

Liz Ashall-Payne, the founder of ORCHA, a British startup that has reviewed thousands of apps, including the National Health Service, says that 68% did not meet the firm’s quality criteria.

What does this mean for users? It means that there should be a strong warning that their data may be shared and that the app might not work. However, for mental health apps to work, two things are needed:

1ne: Data that shows patient outcomes

2wo: Buy-in from the medical community that they can be helpful.

The other huge issue driving the mental health market is that most people are still afraid to talk about their mental health with HCPs or employers. There is a stigma around depression and even anxiety.

For now, however, it’s “try this app at your own risk” as developers look to cash in.