BetterSleep
Not a baby app. It's a sleep app that parents discovered works great for nurseries. White noise, rain, heartbeat, womb sounds, binaural beats - each with its own volume slider so you build your own mix. $60/yr after 7-day trial. Has a baby-specific mode with volume limiting for little ears. If mixing 8 sound layers feels like overkill, Baby Shusher does one sound for $4.99 forever.
BetterSleep started as a general sleep and meditation app for adults, but the sound mixing feature made it a hit with parents. You pick from 200+ sounds - white noise, pink noise, rain, ocean, fan, womb heartbeat, lullabies, binaural beats - and layer as many as you want with individual volume control. Save your mixes for one-tap replay at bedtime.
The baby section includes womb-simulating sounds and a volume limiter to protect hearing. There are also guided meditations and sleep stories, but most parents use it as a fancy sound machine.
The free version is limited. Premium ($60/year) unlocks everything including 300+ exclusive sounds, sleep tracking, and weekly new content.
Compare that to myNoise ($15-20 one-time) which also has deep sound customization but zero baby-specific features. Or Moshi Kids if you want stories instead of ambient sounds.
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