Communication
Focus
Neuro Map90 tracks to choose from
Explore 50 ambient pieces in Focus, Calm, Reset, Sleep and Uplift, plus 40 tracks across seven frequency sections.
Make space for focus and rest
Frequency: Sound by Signalkind
Choose a sound. Make some space.
A listening library for concentration, unwinding and rest. Choose an ambient collection or explore the frequency library, then use the player to shape a listening session that suits you.
Available on the App Store for iPhone and iPad. The native Mac version awaits approval and release.
For a need you recognise.
Choose a sound. Make some space.
Play an ambient piece while reading, then set a sleep timer when it is time to unwind.
A listening library for concentration, unwinding and rest. Choose an ambient collection or explore the frequency library, then use the player to shape a listening session that suits you.
Choose how to use it
You can use Frequency on its own. Add another SignalKind app only when it serves a different need.
What you can do.
Find the sound you want
Search the full catalogue, filter by band or frequency label and keep favourites close.
A player you can settle into
Play, pause, skip, scrub, shuffle, repeat and adjust speed. A sleep timer fades the sound; background controls keep listening accessible.
Listen without streaming
The sound files come with the app. Listen from the bundled library without downloading each session. Apple purchase services remain separate.
Keep a personal listening record
Local statistics, Signal Points and Milestones record your sessions. Track labels describe the library, without promising treatment or a particular neurological effect.
A small, real-world workflow.
An illustrative task you can adapt to your own circumstances.
Choose the kind of session
For example, open the Focus ambient collection for some reading, or look for a favourite nature sound.
Settle into the player
Start playback, adjust the controls and set a timer if useful. Follow the headphone advice for the chosen track.
Finish when it suits you
Pause or let the timer fade the session. Review your own listening record without treating it as a measure of health.
See the app doing something useful.
Real captured screens, with illustrative entries. Open any image for a larger view.
Open full-size screenshot
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Space for the screen you use.
The wide iPad view keeps the navigation at the side.
Open full-size screenshot
The outer display keeps the navigation along the bottom.
Open full-size screenshotListen to a preview.
An ambient listening sample
A sample retained from the existing Frequency website. Press Play when you are ready. No sound starts automatically.
Your devices. Your information.
Device support
The iPhone and iPad app requires iOS or iPadOS 26 or later. The native Mac version requires macOS 26 or later on Apple Silicon or Intel Macs and awaits approval and release. Stereo headphones are required for the five binaural tracks and recommended for the five ADHD-labelled presets; other track guidance varies.
iPhoneiPadMac · awaits approval and release
Privacy and control
Listening history, favourites, milestones, reminders and settings are stored locally. No app account is required. The app does not record microphone audio. Apple handles purchases and entitlement checks.
The audio files are bundled in the app for listening without streaming. Apple purchases, Restore and entitlement updates may require a connection. Optional local app locking uses device authentication.
Read Frequency privacy details →Access and prices.
Choose your App Store country to see its verified purchase options.
Choose your App Store countryOther markets: view the applicable price on the App Store.
Your current location may differ from your Apple Account’s App Store country. Apple’s purchase screen confirms the applicable price and taxes.
Frequency: Sound by Signalkind
A 14-day access window starts at first launch without a subscription purchase. Afterwards, the Collections, Frequency and Guide areas require paid access; earned Milestones and Signal Points remain free.
MonthlyView price on the App Storebilled monthly
AnnualView price on the App Storebilled annually
LifetimeView price on the App Storepaid once
Monthly and annual subscriptions renew unless cancelled through Apple. Eligible subscribers may receive Apple’s separate two-week introductory offer; the purchase screen confirms eligibility and renewal terms. Lifetime is a one-off purchase.
Available on the App Store for iPhone and iPad. The native Mac version awaits approval and release.
Verified country prices checked 7 October 2026. If cost is a barrier, explore free access.
Questions you might have.
Does every track need headphones?
No. The five binaural tracks require stereo headphones; the five ADHD-labelled presets recommend them. Follow the individual track’s guidance for other sounds.
Can I listen offline?
The audio files are bundled, so listening does not rely on streaming. Product loading, purchases, Restore and some entitlement updates still use Apple’s services.
Is it a treatment for ADHD or sleep problems?
No. It is a listening companion. A collection name or frequency label does not establish a health benefit or guarantee a result.
Are the two 14-day offers the same thing?
No. The first-launch app window does not make a purchase. Apple separately offers eligible monthly or annual subscribers a two-week introduction, which renews at the displayed price unless cancelled.
One part of The 4.
Frequency supports make space for focus and rest. The other apps serve separate needs in the same life. Start with one, choose another when useful, and purchase each independently.
Available on the App Store for iPhone and iPad. The native Mac version awaits approval and release.