Big Health CEO Peter Hames had a stressful day Wednesday. His Sleepio app, which was built using Apple’s HealthKit application programming interface (API), was supposed to launch in the App Store with the release of Apple’s new iOS 8 mobile operating system. Wealth and fame would follow. And people would sleep better.

But like so many other HealthKit app developers that day, Hames’ hopes were dashed when Apple informed developers that the HealthKit health data platform was buggy and would not be fixed until the end of September at best.

But Hames was determined. His team scrambled to unhook the Sleepio app from HealthKit and release it in stand-alone form. Sleepio is now live in the App Store.

As Hames explained to me, the Sleepio app is meant to create a cognitive therapy approach to improving the user’s sleep. That is, the app will ask the user questions about sleep patterns then provide information on how to improve. It’s the same kind of dialog one would have with a sleep therapist, but without the therapist, Hames explains.

The cognitive approach comes from Hames’ conviction that both the healthcare system and consumers often default to various types of pills to cure our problems.

“A few years ago I developed insomnia,” Hames told VentureBeat. “But my doctor just kept trying to give me sleeping pills, and I didn’t want to take pills.”

Cognitive therapy, on the other hand, worked. “I have a behavioral psych degree so I was looking for a way use that approach,” Hames said. “I was a  using a book written by sleep expert Professor Colin Espie, and within weeks my insomnia was cured.”

Hames teamed up with widely known Oxford sleep researcher Espie to develop the line of questions, suggestions, and other information contained in the Sleepio app.

The point of the Sleepio app is to make these tried-and-true cognitive techniques more accessible and engaging, even fun. It takes a holistic approach, suggesting a personalized program that focuses on sleep schedule, thoughts, and lifestyle.

Not only does Espie’s research provide much of the content for the apps, but he inspired the app’s central character. When you open the app, you see an animation of a shortish, dark-haired, academic type — who speaks to you in a calming Scottish accent. He also has a funny little dog name Pavlov that has a habit of falling asleep unexpectedly.

Hames says that tests of the techniques suggested by the app have caused users to fall asleep 56 percent faster, have reduced nighttimes awakenings by 63 percent, and have boosted daytime energy and concentration by 58 percent in test patients.

Sleepio already can import sleep data from the Jawbone UP wearable, but the app doesn’t depend on wearables data to work. Wearables data (like sleep duration, wakeups, etc.) is just one input that can be used to inform the sleep advice generated by the app itself.

Hames says the app will get similar data from other sleep-tracking wearables that integrate with the HealthKit platform once it launches. And it will get much more interesting from in the future. The Sleepio app might begin to pull in things like caffiene intake data from HealthKit-connected diet apps, or exercise data from HealthKit-connected fitness apps. Diet and exercise have a marked effect on sleep, and data about those things could dramatically enhance Sleepio’s ability to improve users’ sleep.

“This just wasn’t possible before,” Hames says. He’s noticably excited about HealthKit, and believes it can really have a positive effect on big-picture health issues in the future. Hames and his team plan to build the HealthKit features back in to Sleepio once the platform is up and running.

And insomnia may be just the first problem that Big Health addresses with congitive therapy apps. Hames points out that other problems like depression and anxiety can be addressed the same way. So, yes, a “Depressio” app may be in Big Health’s future.

The Sleepio App is available for free on the App Store for iPhone and iPod Touch. The app includes 7 days free access after which users choose an “Instant Sleep Help” program for $4.99 a month, or a “Long Term Sleep Improvement” program at $149 for 12 weeks access. They can also continue using Sleepio for free, which gives you access to the “Sleep Diary” and “Your Schedule” features only.

Big Health is backed by Index Ventures, Forward Partners, and several angel investors.