I built Rhythm. Check the details against each app's own pricing page before you decide. Longer write-ups: Rhythm vs Huckleberry and Rhythm vs Nara.

Rhythm Huckleberry Nara Baby
Price RhythmFree on one device, including predictions. Sync, partner invites, and backup are $5/mo or $45/year per household HuckleberrySyncing across caregivers is free; SweetSpot predictions need Plus at $11.99/mo, or $68.88/year billed annually Nara Baby7-day free trial, then $9.99/month or $99.99 once for lifetime. One payment covers all caregivers and children
Sleep / wake guidance RhythmComputes the wake window from your baby's own logged days, on your phone, and labels whether each number came from an age default, logged sleep, or your override HuckleberryAge-appropriate sleep guidelines plus your baby's own logged sleep, per Huckleberry's SweetSpot explainer Nara BabyYou choose the wake windows (Nara publishes an age chart) and nap reminders shift based on when the last nap ended
Account required RhythmNo - open the page and log the first event; an account is only for sync HuckleberryYes Nara BabyYes - Nara's setup guide says you create an account on first launch
Events you make yourself RhythmBuild your own event types, instant or timed, with the detail fields you pick HuckleberryNot in Huckleberry's App Store listing Nara BabyA set activity list you can trim, but not add to - there's no builder for new event types
Breast milk stash RhythmFreezer inventory with oldest-first order and expiry dates from CDC storage guidance HuckleberryNot in Huckleberry's App Store listing Nara BabyPumping sessions, yes; a freezer inventory isn't something Nara describes
Works offline RhythmYes - logging and predictions both run on-device HuckleberryLogging works offline Nara BabyNot something Nara's pages address
Export your data RhythmCSV or JSON from Settings, whenever you want it. Imports the Huckleberry and Nara Baby CSVs HuckleberryCSV, emailed to you, one file per child Nara BabyCSV per child from Account, Family, your child's name
Where your data lives RhythmOn your device first; a copy reaches my servers only if you turn on sync HuckleberryOn their servers Nara BabyBehind your Nara account, synced through Nara's service

Sources and check dates for the Huckleberry and Nara rows (Nara's pricing was last checked September 30, 2026; the free-use cutoff for existing users isn't confirmed) are on the Rhythm vs Huckleberry and Rhythm vs Nara pages.

Questions

Which of these three is cheapest?

Rhythm's tracking and predictions are free on one device, with sync at $5/mo per household. Nara Baby is $9.99/month after a 7-day trial, or $99.99 once for lifetime. Huckleberry's caregiver sync is free, but its SweetSpot predictions require Plus at $11.99/mo.

Which one computes sleep predictions automatically?

Rhythm and Huckleberry both compute a prediction from a baby's logged sleep and age. Nara Baby instead has you choose wake windows yourself from a published age chart.

Do any of them require an account to start?

Rhythm does not; open the page and log the first event, and an account is only needed for sync. Huckleberry and Nara Baby both require an account from setup.

Can I import from Huckleberry into Rhythm?

Yes. Export your Huckleberry data and use Settings, Import Data, Huckleberry in Rhythm; the import guide lists exactly what comes across.

Can I import from Nara Baby into Rhythm?

Yes. Export each child's CSV from Nara (Account, Family, your child's name, Export Data) and use Settings, Import Data, Nara in Rhythm; the import guide lists what comes across and what stays in Nara.

No account, no install, nothing to uninstall if it is not for you.

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