Saying OK to Sex? There’s an App for That

The apps are aimed at young people, particularly college students, who are comfortable using technology to communicate, surrounded by an array of potential sexual partners (and often alcohol), and relatively new to the nuances of sex. Sexual-assault allegations aren’t uncommon on campuses: One in five women say they have been assaulted while in college, according to the Campus Sexual Assault Study, funded by the U.S. Department of Justice. One in 16 men say they have. Often, those who are accused of sexual assault claim the sex was consensual, while those who say they were assaulted said they never agreed to the encounter. The problem has prompted at least four states—California, New York, Connecticut and Illinois—to pass laws in the past four years that require schools to teach students about affirmative consent, stressing that the message should be “yes means yes,” rather than the old “no means no,” according to the Affirmative Consent Project, a nonprofit based in Jacksonville, Fla., that works to stop sexual assault in colleges and high schools.

Potential partners sometimes disagree on what constitutes consent: At least 40% of current or recent college students believe that undressing, getting a condom or nodding yes establishes consent for sexual activity, and at least 40% said those same actions do not, according to a 2015 Washington Post-Kaiser Family Foundation poll. Young men may misinterpret a woman’s style of dress or her flirtiness to mean she wants to have sex, even when she declines. Often, when a woman says no, a man takes that as a challenge to push harder. “Some men hear these refusals but they choose to ignore them,” says Kristen Jozkowski, an associate professor of community health promotion at the University of Arkansas, who studies sexual violence and consent.

Proponents of the consent apps say they are meant to address these issues—protecting both parties by encouraging a frank discussion over what is desired and then recording a clear agreement. “A lot of problems come from miscommunication,” says Alison Morano, founder of the Affirmative Consent Project. “If you have an actual conversation, it will help you make a decision you won’t regret in the morning.”

Cody Swann, CEO of Gunner Technology, which owns uConsent, says he designed the app so that two people have to be in the same room together when they give consent, in order to facilitate a discussion. One person types what he or she is requesting into the app, but must orally tell the other person what it is. That person then types into his or her phone what he or she will agree to, and a bar code is generated. The two people then hold their phones together and the app captures the bar code and makes sure that what was requested matches what was granted. This info is then encoded and stored securely in a cloud-based database.

But psychologists and other experts say the apps ignore the complexities of consent, which can shift from moment to moment. The idea that a person who gives consent to have sex at 8 p.m. will absolutely still want to have sex at 10 p.m., or even 8:30, is unrealistic, says Helen Fisher, a biological anthropologist known for her research scanning the brains of people in various stages of love. “You might say yes to the overall interest in sex with somebody, but then you get with them and they don’t smell good or they act strange or they get aggressive and you are frightened,” Dr. Fisher says. “We are constantly adding up the pros and cons of the situation at hand and changing our mind.”

Critics also say the apps are too narrow in scope—they allow people to give a blanket consent to sex, rather than specifying exactly what they do and don’t agree to do. And they worry that they will be seen as a substitute for an open and honest conversation about sex.

“Consent requires a complex communication,” says Paul Reynolds, a reader in sociology and social philosophy at Edge Hill University in Ormskirk, England, who has studied consent for 20 years. “In order to make a decision about whether you want to have sex with someone, there should be a conversation about what kind of sex is acceptable and whether it will be a one-time experience or long-term relationship, so you know what you are getting into. These apps don’t do that.”

There also are legal concerns: What happens if one partner decides that he or she no longer wants to have sex, after giving consent on the app? Some apps have no way for people to withdraw their consent. Others require the person to log back on to withdraw it, even though this might be difficult to do in the moment. An oral withdrawal of consent should be honored, of course. But if an assault does occur, that original recorded consent could be used against the victim in court, experts say. “If sex was forced or changed and someone is now saying she didn’t want to consent, you now have this video evidence saying, ‘No, you said yes,’ ” says the University of Arkansas’s Dr. Jozkowski.

And what about privacy issues? Some apps, like uConsent, don’t require users to log in with any identifiable information and encrypt the consent agreement and store it in the cloud, not on people’s phones. Others have access to billing information and your phone’s contact list. It’s always good to read the app’s privacy policy.

Mr. Swann, of uConsent, declined to discuss how many times the app has been downloaded. He says he is looking to improve it with features such as a panic button that someone could hit to withdraw consent instantly (right now there is no way to do this on the app) and a state-of-mind test, such as a math problem, that allows the app to gauge if someone is drunk.

“This is not a legally binding contract,” Mr. Swann says. “This is like a digital handshake agreement. You talk about what you are agreeing to, and then you shake on it.”

Write to Elizabeth Bernstein at elizabeth.bernstein@wsj.com or follow her at Facebook , Instagram and Twitter at EBernsteinWSJ