MORTON — While a wildly popular smartphone game goaded hordes this summer to search the world for virtual characters on a screen, a group of local developers worked to bring the real world to visually impaired people through the same types of devices.

Both Pokémon Go, the game that garnered global attention with an estimated half a billion downloads since its release, and Cydalion, an app developed by Morton-based Float that launched Tuesday, operate on the same underlying principle — augmented reality.

Both programs take information gathered by smartphones and tablets, such as location data from sensors and images of the surroundings from cameras, to allow interactivity with the immediate environment.

While Pokémon Go uses near-ubiquitous smartphone technology to entertain, however, Cydalion employs an emerging set of Google-designed hardware and software for a more practical purpose: to detect obstacles in the environment and warn visually impaired people in real time of their approach.

"This is something quite different from other apps in the augmented reality space,” said Chad Udell, managing director of Float. “Many developers are using this new technology to create video games or other entertainment, but we are using it to make a real impact on those who are visually impaired in day-to-day life."

Cydalion surveys areas in front of an array of sensors and emits a series of tones corresponding to the location and distance of obstacles, with different tones for objects to the right, left or center, high-pitch sounds for head-height barriers, and low-pitch emissions for tripping hazards. The tones vary in frequency according to the distance of the objects from the device.

The app's sounds can be customized, and a display on the screen visually represents warning areas with options for color-blind individuals. Float recommends using a vest or lanyard to hold the device perpendicular to the ground at chest level and bone conduction headphones that emit tones without blocking ambient sound.

Matt Forcum, Float's lead designer of the app, said early iterations of the program included spoken feedback, but the verbal warnings proved less intuitive than tones in stereo sound.

"We were really kind of surprised to find that when we took that out completely, people picked up on it really quickly," Forcum said.

Float partnered with Illinois State University's College of Education and Student Access and Accommodation Services, as well as the student organization Braille Birds, to test the app and receive feedback. With much of the development work done by mid-September, Float created an obstacle course out of cardboard boxes in the Alumni Center to test Cydalion's real-world application.

The app is named after Cedalion, the figure in Greek mythology who stood on Orion's shoulder while he was temporarily blinded and guided him toward the rising sun to restore his sight.

A hardware system, called Tango, with two camera lenses, an infrared sensor and supporting software developed by Google gives apps such as Cydalion the ability to detect distances between devices and objects in the environment in real time as the device moves.

The first commercially available smartphone with the Tango architecture — the Lenovo Phab 2 — will debut later this month. Its capabilities also would allow designers, for example, to overlay different materials or patterns on an object viewed through the camera and see the results in three dimensions on the screen.

And both the hardware and the app have room to grow with technological advancements, Udell said. The hardware components some day could fit into wearables such as glasses or hats, while the software could incorporate facial recognition to give visually impaired people notifications when they encounter familiar people.

"There's opportunities long term for an application like this to recognize environmental signatures," Udell said.

And Cydalion, despite the ancient implications of its name, is already considerably advanced beyond the most commonly available tools for visually impaired people today.

"The tools really haven't changed in 100 years," Forcum said. "It's a cane and a dog, essentially."

Matt Buedel can be reached at 686-3154 or mbuedel@pjstar.com. Follow him on Twitter @JournoBuedel.