Comparison

Quell vs Calm Sounds

Price, ratings, monetisation and update history for both apps, side by side โ€” with what reviewers say about each.

Head to head
About

Quell

Features
Read full description

Quell is a deep-focus app with one job: help you sit down and do one undivided thing. No streaks. No badges. No feed. You tap Begin, a calm arctic ring starts counting up, and a 40 Hz binaural beat plays underneath. When you are done, you end. That is the whole ritual. WHY 40 Hz 40 Hz is the gamma band โ€” the brain rhythm tied to attention and memory, and the most-studied frequency in sound-based focus research. Quell generates it live: two pure tones, one slightly different in each ear, that your brain fuses into a single 40 Hz pulse. WHAT IT DOES - A 40 Hz binaural beat, generated live on your device. Two pure tones on a deep, warm carrier (130 Hz left, 170 Hz right). It needs stereo headphones to create the beat. - An optional coach voice. Short, grounded lines, spaced minutes apart, that nudge you back when your attention drifts. It is sports-psychology self-talk, not generic meditation, and it is a natural recorded voice, not a robotic one. - Optional music under the beat. Four moods of original, AI-generated tracks (lofi days, lofi night, global beats, ambient) that sit quietly beneath everything. Off by default. - A count-up timer. No fixed length, no pressure. The session lasts as long as you stay. THE SCIENCE, HONESTLY We lead with 40 Hz because the research is real โ€” it is the gamma approach popularized on the Huberman Lab podcast. A 2022 meta-analysis found binaural beats gave a small but significant lift to attention and memory, and a 2025 study confirmed that a 40 Hz beat measurably entrains the brain while improving attention. But we will not oversell it: not every study agrees, and the effect varies from person to person. Treat the 40 Hz tone as a low-risk way to settle into deep work, not a guarantee. DESIGNED TO DISAPPEAR Quell is dark, still, and quiet on purpose. The only bright thing is the ring. It keeps playing while your screen is off, with controls on the lock screen, so you can put the phone down and work. PRIVATE BY DESIGN Everything runs on your device. No account, no sign-in, no tracking, no analytics, no servers. Your settings stay on your phone. FREE AND PAID The 40 Hz beat and the timer are free, forever. A single one-time purchase unlocks the music moods and the coach voice. Pay once, it is yours. No subscription. Quell. Quiet the noise.

About

Calm Sounds

Features
Read full description

Calm Sounds is a tiny sanctuary for your ears. Tap the glowing orb and sink into deep, seamless relaxation audio: rich brown noise, a low 60 Hz drone that swells like slow breathing, or both layered together. - Endless, truly gapless sound - no loops, no seams, no interruptions - Three moods: Brown Noise (dark and cozy), Drone (deep and meditative), or Both - Sleep timer (15, 30, or 60 minutes) with a gentle minute-long fade-out - Keeps playing with your screen locked, with lock screen controls - No account, no ads, no tracking - just sound Made with love for anxiety relief, focus, and falling asleep.

Screenshots

Quell4 screens
Calm Sounds3 screens

Verdict

The call

The clearest difference is in-app purchases: Calm Sounds at none against Quell's 1. On price, ads, device support and iOS requirement there is nothing between them.

Scored on Price ยท Rating ยท Positive reviews ยท Number of ratings ยท Update frequency ยท Ads ยท In-app purchases ยท Monetization ยท Best chart rank ยท Devices ยท Requires iOS

CostPrice ยท In-app purchases ยท Ads ยท Monetization

Both are free to download. Quell sells 1 one-off in-app purchase. Calm Sounds asks for nothing beyond the download.

Scorecard1 real difference ยท 5 level
Quell versus Calm Sounds: the parameters behind the verdict, then further details
ParameterQuellCalm Sounds
PriceFreeFree
Update frequencyDailyโ€”
AdsNoNo
In-app purchasesYesNo โ€” better
DevicesiPhone, Mac โ€” betteriPhone
Requires iOS17.017.0
Further details โ€” not scored
Size58 MB0 MB
Age rating4+4+
DeveloperOleksandr Pavlovkrystina athanasiadis

In-app purchases

1 purchases

Quell

One-time1
  • Quell Unlock$9.99
None

Calm Sounds

No in-app purchases

Questions

Is Quell free?
Quell is free to download, with in-app purchases available.
Is Calm Sounds free?
Calm Sounds is free to download, with no in-app purchases.
Do Quell or Calm Sounds have ads?
Neither Quell nor Calm Sounds shows ads.

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