COO - Baby Sound Therapy
What is COO?
Sound playlists for parents and caregivers to settle a crying infant, with six sound environments and an optional sound.
COO is a sound app for parents and caregivers, offering layered audio playlists meant to help settle a baby. Each playlist combines pink or brown noise, a binaural drone tuned to a Solfeggio frequency, a 68 bpm heartbeat, and a soft melodic overlay. The listing describes six sound environments, including Calm & Settle, Big Feelings, Bonding, Immune Support, Teething & Comfort, and Sleep Wind-Down.
Pricing. COO is free to download, with in-app purchases on the App Store.
Good for
- Settling a crying infant during evening or night hours
- Calming yourself while walking or pacing with a baby
- Winding down a baby toward sleep at bedtime
Screenshots
Why this app is in A tier
A tier follows from that score within this list. The full explanation, as data.
COO scores 81 out of 100: rating 100, rating count 45, App Store search rank 78, update recency 100. The four parts are averaged and A tier follows from that score within this list.
Description
Some nights you're pacing the hallway, the backyard, the whole neighborhood with your crying infant, running out of ideas and running low on yourself.
COO was built for that moment.
It's a sound companion for parents and caregivers - layered audio designed to help you settle your baby by first settling yourself. When your nervous system regulates, your baby's follows. This is co-regulation: the science behind every instinct you already have.
Six sound environments, each designed for a specific moment:
Read more
- Calm & Settle - for the everyday overwhelm
- Big Feelings - when emotions are running high
- Bonding - skin to skin, fully present
- Immune Support - frequency support during illness
- Teething & Comfort - for the hard nights
- Sleep Wind-Down - the long, slow drift into rest
Each playlist layers pink or brown noise, a binaural drone tuned to a Solfeggio frequency, a heartbeat at 68 bpm, and a soft melodic overlay, set at a comfortable default volume for each layer.
COO Premium unlocks all six playlists, the sound mixer, Play All with a drag-to-reorder queue, and extended sessions for an effortless hands-free experience. Try all of it free for 7 days, no card required, then keep it for a one-time $3.99 whenever you are ready.
Made for caregivers, by a caregiver.
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Questions about COO
Is the app free to install?
It is free to download. The description says COO Premium unlocks all six playlists, the sound mixer, Play All with a drag-to-reorder queue, and extended sessions.
Does it need a payment method to try Premium?
The description says Premium can be tried free for 7 days with no card required, after which it can be kept for a one-time $3.99 payment.
What sounds are included in each playlist?
The description says each playlist layers pink or brown noise, a binaural drone tuned to a Solfeggio frequency, a heartbeat at 68 bpm, and a soft melodic overlay, at a default volume for each layer.
Is COO free?
COO is free to download, with in-app purchases.
Is COO right for me?
COO is built for settling a crying infant during evening or night hours, calming yourself while walking or pacing with a baby, winding down a baby toward sleep at bedtime. It sits in the sound therapy list on AppTierList.
Is COO worth it?
COO is A tier, ranked #8 of 17 sound therapy apps with a score of 81 out of 100, from a 5.0 App Store rating across 3 ratings. It is in the list's top tiers; 7 apps rank above it.
How does COO compare to Healing Frequency Sleep Sounds?
COO is A tier at 81; Healing Frequency Sleep Sounds is A tier at 85. Healing Frequency Sleep Sounds ranks higher. COO is free to download, with in-app purchases, Healing Frequency Sleep Sounds is free to download, with in-app purchases.
How often is COO updated?
COO was last updated on 2026-09-09, 66 days ago.
Alternatives
Most similar
Top rated in Sound Therapy
Categories
All the facts
Ranking
- Lists
- Sound Therapy (A tier, #8) · Relaxation Sounds (D tier, #25) · Relaxation (#92, beyond the tiered top)
- Tier
- A (Excellent)
- Score
- 81 / 100
- Rank in list
- #8 of 17
- Ranking certainty
- early: few ratings or search ranks so far
Ratings
- App Store rating
- 5.0 out of 5, every App Store country
- Ratings
- 3
App
- Price
- Free + IAP
- App Store category
- Health & Fitness
- Current version
- (66 days ago)
- Size
- 133 MB
- Requires
- iOS 15.0 or later
- Age rating
- 4+
- Languages
- 1
- Runs on
- iPhone, iPad
Links
- Developer pages
- Support · Privacy policy
- Maker
- not verified
- As data
- JSON · why it ranks here
App Store data read · ranking