At LISNR, your privacy has always been important. Since our technology’s birth, we’ve taken measures to ensure our customers’ privacy and security. Following strict guidelines outlined by the Electronic Communications Privacy Act, we continue to be committed to providing our customers with the best experience possible.

We encourage you to read the summaries below and contact us if you have any questions.

How Our Technology Works

LISNR is the only data-over-audio solution that uses ultrasonic, inaudible sound waves to connect and activate various experiences on any device. These high frequency sound waves, which we call SmartTones™, can transmit data using a speaker to and between any smart devices with a microphone. Compared with other audio technologies, LISNR is the only true data-over-audio solution. Our technology completely takes away the need for any audio recording, server calls, or other forms of data connectivity like Wi-Fi, cellular, or Bluetooth to enable LISNR functionality.

Customers embed our SDK on the backend of an application to enable any device with that application to listen for SmartTones. These SmartTones carry bits of data that are demodulated when detected by our SDK.

LISNR SmartTones are comprised of FSK audio signals varying between frequencies of 18.75 kHz and 19.2kHZ, making them inaudible to the human ear. Our SDK only recognizes sounds that fall between that frequency range.

Most sounds that we hear every day, like the sound of a human voice, simply aren’t detectable by LISNR as they fall well below our high frequency range and are filtered out completely by our technology.

We Do Not Save or Record Any Audio or Personal Data

We do not collect or share any personally identifiable information, nor does LISNR record any audio on the device. We rely solely on the microphone to detect and decode our SmartTones. All audio received from the microphone is filtered to only include the high frequency, inaudible sound waves that comprise our SmartTones. LISNR receives and buffers approximately 10 seconds worth of the filtered inaudible audio. Once this data is processed and analyzed, it is overwritten by new data and cannot be saved or recovered in any way.

Audio Data Is Not Passed Over the Network

All audio-related processes are handled locally on the device and never passed over the network. LISNR does not have the capability to deliver audio to a server or move it off of the device in any way.

You Are In Control When Your App Listens for Our SmartTones

LISNR requires access to the device’s microphone to “listen” for SmartTones. Microphone permissions must be granted by users and can be turned off and on at any time at the convenience of the app user in the application settings. We always counsel and require all of our clients to clearly communicate microphone usage to users.

As we continue to grow as a company, we pledge to continue:

      • To always be transparent on data we’re using.
      • To always ask for permission when sending content.
      • To always follow best practices in our security procedures.

Your feedback and support is, and has always been, important to us. Please feel free to reach out and email us at with any questions or comments. In the meantime, you can review our privacy policy.


~Rodney Williams,

CEO and Co-Founder,

and #TeamLISNR

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