A bedtime storyteller that lives in your phone.
Tap once. Whisper a wish. Hear a different fairytale every night — generated entirely on-device, with no internet, no accounts, no data leaving the phone.
What is Baku AI?
Baku AI is an iPhone bedtime-story app for children ages 3 to 8 that generates a different fairytale every night, fully on-device with Google's Gemma 4 model. Pick a wish, tap once, and Baku reads in a soft natural voice for 5–8 minutes — in English, Simplified Chinese, or Spanish. The screen dims so children listen with eyes closed. No internet, no account, no subscription, no ads, no data collection — COPPA and GDPR-K compliant by design. Built-in lullabies, meditations, and ambient sounds are all included. One-time $5.99 purchase, lifetime access. Optional $0.99/month unlocks Personal Voice (your own recorded voice reads the stories).
The bedtime app I wished existed for my own daughter.
1 tap. No screen time.
Open. Pick a wish. Press play. The screen goes dark and Baku reads. Your child listens with eyes closed, the way bedtime stories were meant to be heard.
Truly offline. Truly private.
After the first launch, the AI runs entirely on your phone. No server, no cloud, no telemetry. On a plane, in a tent, at grandma's house — Baku still works.
A new story every night.
Same wish, fresh story. Baku composes a new tale on the spot from a thousand fairytale beats — so 'I want a dragon' tonight is not the dragon from yesterday.
Safe by construction.
12-language safety filter, parent-curated wish list, no chat input. There is no way for the model to be steered into something it shouldn't say. I built this for my own kid first.
Three taps to a story.
From wish to first sentence in under five seconds. After that the screen goes dark and you can put the phone down.
Pick a wish
From a curated list — A friendly dragon. A lost moon. Grandma's garden. You can also pre-write your child's name and favourite things in Settings, and Baku will weave them in.
Baku composes
Gemma 4 runs on the Neural Engine and writes a 5–8 minute fairytale, on your phone. No server roundtrip. No internet. Even the safety filter is local.
Baku reads
Apple's natural voice narrates softly while a slow page-turn paces the story. The screen dims to almost-black so it doesn't keep your child awake.
Watch Baku spin a fairytale, in real time.
Pick a wish on the left. Below is the story Baku composed and read out loud, on the device, while you waited.
Generated locally on Apple Neural Engine. Same wish never produces the same story twice — Baku composes from scratch.
Small app. Carefully made.
How Baku is different.
I'm Jingyang. I read to my daughter every night. After about the eightieth re-reading of the same picture book, I started wondering whether my phone could just… write a new one.
Then I worried — most kid apps quietly send everything to the cloud, log every prompt, push notifications, and try very hard to keep my kid on the screen.
I wanted the opposite app. Tap, listen, sleep. Nothing leaves the phone. No subscription. No tricks.
I shipped it. It is now my daughter's favourite app, and the one I trust the most.
100% on-device. 0 data collected. 1 person built it.
If that ever changes, I will write it on the homepage.
— Jingyang Ye, Baku AI
Built in San Francisco, 2025–2026
Honest answers.
Does Baku really work without internet? +
Yes. After installing, you can put the phone in airplane mode and Baku runs exactly the same. The Gemma 4 model lives on your device. Voices are Apple's free natural voices, also on-device. The only network calls are App Store updates.
What model does it run? +
Google Gemma 4 (a small, open-weight model), quantised and converted to Apple's Core ML format so it can run on the Neural Engine. Runs comfortably on iPhone 12 and newer; works on older devices but more slowly.
Is my child's data ever uploaded? +
No. There is no analytics SDK, no crash reporter, no telemetry. Your child's name, age, favourite themes, and saved stories live in the app's local sandbox. They never leave the phone unless you explicitly export a story.
Why $5.99 instead of a subscription? +
Because subscriptions for kids' content turn into a guilt loop. Pay once, keep it forever, including all future story themes and language updates. If the app ever stops being maintained, you still have it.
How are stories kept safe? +
Three layers. First, kids never type — they only tap from a parent-curated wish list. Second, generation is constrained to bedtime themes (no horror, no death, no violence). Third, every sentence runs through a 12-language safety filter before being read aloud. If anything is flagged, Baku quietly regenerates.
What ages is it for? +
Designed for 3–8. Younger kids enjoy the voice and the rhythm; older kids enjoy specific wishes ("a friendly dragon called Pip who likes mango"). It works in English, Simplified Chinese, and Spanish.
Will there be Android? +
Maybe. iOS first because the Neural Engine is the easiest place to run on-device models well today. If enough Android parents ask, I'll port it — but I won't ship something slow.