“I can’t tonight, I have chlamydia.” With those words Miranda, a character on the racy television series Sex and the City, doused her partner’s lust and reminded the TV audience of just how awkward conversations about sexually transmitted diseases can be.

Miranda’s admission aired 13 years ago, but the challenges of negotiating those conversations persist. More recently, the marketplace of ideas has churned out a bevvy of digital tools meant to help consumers anonymously inform past sex partners that they have been exposed to an STD (often via no-fun e-cards that carry the bad news) or to help people easily access their own test results—both for their own reference and to share with bedmates.

All told, about 10 such Web- or phone-based electronic services have come online, and more are in the works. To varying extents they all either help provide people with STD test results or allow them to anonymously inform partners of risk. Don’t Spread It, inSPOT and So They Can Know, for example, send anonymous exposure notifications to partners of infected individuals. And they have garnered the early approval of some health experts. (The San Francisco Department of Public Health was an early partner in developing inSpot almost a decade ago, easing STD diagnosis sharing among sex partners. Also, the Baltimore City Health Department is now working with the makers of So They Can Know to create their own portal to allow people to see their own STD test results online and separately inform at-risk partners of the need to be tested.) And services called Chexout and ChecMate allow health providers to securely upload test results, which are then shared privately with patients who subscribe.

A new free mobile app, the first of its kind, provides broader tools than the others, earning it praise from public health experts for promoting STD testing and awareness. The cutting-edge program, however, is also stoking some concerns about privacy, legality and what message its services send. It is called Hula, like the Hawaiian dance, because, its developers say, it helps “get you lei’d.” (Also, lest you forget, “horizontal hula” is slang for sex.) The app provides names, addresses and other information about local STD testing services, and collects the results in one place. To access your results or show them to others in a fairly light-hearted way, you go to a screen covered by the image of a closed zipper and unzip the image with your finger, gradually revealing the information underneath. Or, you can “friend” others to allow them to securely see the results via their digital devices. The app also lets users review STD testing centers with Yelp-like reviews about their experiences.

The app aims to address what its backers call a “broken system,” acting as the middleman between a user and the clinic by helping patients get their test results (when they otherwise may not) and interpreting them so patients can understand. With a user’s permission, labs upload raw results to Hula. Then a trained Hula employee taps the results into a set template so that it will be understandable. Instead of a syphilis test finding saying you are “nonreactive,” for instance, the app will say that the person is “negative” for syphilis. Because of understaffing at health clinics across the country, a de facto norm has been “no news is good news”—with clients either being explicitly told or assuming that if they do not hear about their results, there is nothing wrong. Yet positive results can fall through the cracks that way. An automatic app like this can ensure that results get to their destination. And Hula’s backers say they hope that the app will promote further testing, because it sends out reminders of the need for regular checkups.

Hula’s medical advisor, Jeffrey Klausner, says he sees the app as an important public health tool. The U.S. Centers for Disease Control estimates that a staggering 20 million new STDs are diagnosed in the U.S. every year, costing the U.S. health care system some $16 billion in medical costs annually. Right now, more than 110 million sexually transmitted infections are circulating among men and women across the nation. “When you are thinking about the millions of people in the U.S. who have infections and don’t know it, an effort that will promote easier screening and change the way people deal with test results is going to help,” he says. Klausner, a physician, was the former director of STD Prevention and Control Services at the San Francisco Department of Public Health and is a current professor of medicine and global health at the University of California, Los Angeles.

The CDC and public health officials also acknowledge the potential benefit of apps that make people more aware of the need to be tested for STDs and to share the outcome with sexual partners. Such actions are needed more than ever these days, the CDC notes, with people now looking to phone apps to seek sex partners. Mary McFarlane, a research behavioral scientist in the CDC’s Division of STD Prevention, predicts, too, that new mobile apps could help to reduce STD cases if they reduce the stigma of infection and of seeking sexual health care. But whether this type of app would provide the most accurate information and adequately protect patient privacy has yet to be determined, the CDC told Scientific American in an email.

When asked about Hula, public health departments have similarly been somewhat measured in their support. Susan Philip, chair of the board of directors of the National Coalition of STD Directors and director of the Disease Prevention and Control Branch of the Population Health Division at San Francisco’s public health department, called the model “interesting and provocative,” echoing CDC’s approval of efforts to improve contact with people who are at risk of STDs who may be more likely to use such apps. Still, legal concerns about turning over STD results to someone other than the patient prompted her city’s STD testing services to turn away patients’ requests to send test information to them via Hula—even though Hula facilitates filling out a Health Insurance Portability and Accountability Act form that gives clinics permission to share the data for each Hula user. “We are speaking with our city attorney about it and getting some clarifications. A lot of people are in the clarification stage,” Philip says.

Another concern that gives some public health experts pause is that a list of negative test results can give the test-taker and the individuals’ sex partners a false sense of security. Hula’s test data comes with time stamp, but even if the tests were fairly recent, they don’t necessarily mean the person is infection-free at the time they get the data. The individual could have unknowingly become infected after the test, could have taken a more recent test that was not reported to Hula or might have been tested in the period before an existing infection would show up in the results. Take HIV infection, for example: the immune system can take several months after viral exposure to make enough anti-HIV antibodies for the standard clinical HIV test to detect and indicate infection. Each time Hula posts results it warns users about such time-sensitive problems, states that a negative result does not guarantee a person is STD-free and urges people to “play safe.” But health officials still worry that some people may be misled by the initial impression that a tested person who is actually infectious is in the clear. “It’s an innovative concept and it’s targeting the right age, but my concern is it gives the suggestion that you are [STD-] negative,” says Patrick Chaulk, acting deputy commissioner for the Baltimore City Health Department Division of Disease Control.

“The message we want people to take is we definitely want people to get tested but not to take [good results] as a carte blanche to do anything they want,” he says. Baltimore has already recognized that it needs to improve its communication of STD results akin to Hula’s mission, admitting that to contact everyone who has taken a test is not easy. “We try to get ahold of everyone. We have about 33,000 tests a year in two clinics, so our priority is to contact everybody who has a positive test—gonorrhea, chlamydia, syphilis and HIV,” he says. Boosting users’ access to negative and positive results is why Baltimore’s health department is currently partnering with Sexual Health Innovations to build a Web site that will allow clinic users to access their test results by a laptop or a smartphone. So They Can Know is also helping the city to set up a text messaging or e-mail service that will send out the results that way, if users consent to such services. No STD clinic patient has yet asked about Hula, Chaulk says.

For its part, Hula is currently offering its services for free, although it hopes to eventually be able to turn a profit. Right now, its makers are looking for ways to expand the uses of the app to make further inroads into preventing STDs. It is working with the Los Angeles Unified School District to promote teaching teens about STD testing and safe sex, and teachers have the option to let students know that Hula is out there for those who are or will later become sexually active.

Hula is also hoping that it can help to reduce the risk of sex with people met through the proliferating location-based dating apps. Last month it announced that it was partnering with the gay dating app MISTER, which has a geolocator that helps men find other men by location. MISTER is currently publicizing the Hula service on its app and encouraging users to tap it to find local testing centers and obtain test results. MISTER is also encouraging users to link to Hula from within their profiles, making their test results available to online “friends.” Verified test results on gay sex apps would be a big change from current approaches, where it is common for individuals to self-report that they are HIV-free on their profiles. “In the not too distant future you’ll be able to see a badge on someone’s dating profile showing they’ve verified STD status by Hula,” says Hula founder and CEO, Ramin Bastani. “That can help you make better decisions about how you want to connect.”

But Carl Sandler, CEO of MISTER, says they are currently “proceeding carefully” about how to further integrate it into their app. “Verified results should be the start of a longer discussion, not a litmus test,” Sandler says. “I think in the future people will be more likely to ask for verified data, but that’s not something we’d require. There is too much prejudice and stigma against STDs and HIV, and verified data is only part of the safer sex equation.”

“When it comes to STD prevention, Hula is in no way a ‘silver bullet,’ and we never suggest that our users are STD-free,” Bastani says. “Like a condom, Hula is just another tool in your STD prevention toolbox. We feel the tools we provide are much better than the status quo—which is either self-reporting or not reporting at all. In our view, some information is much better than no information.”