daatlas — Open-Source Diabetes Data Bridge for iOS

Your CGM, pump, and wearable data. In Apple Health. For free.

daatlas is a privacy-first iOS app that unifies fragmented diabetes data — glucose readings, insulin deliveries, carbs, and Oura Ring vitals — into Apple Health's unified timeline. No backend, no account, no subscription.

View on GitHub

The problem

If you manage diabetes with a CGM and an insulin pump, your data is already scattered. Add a wearable like an Oura Ring and it gets worse — glucose in Nightscout, sleep in Oura, activity somewhere else. Apple Health could be the single source of truth, but nothing bridges all of it automatically.

The first solution

It started with daatlas-healthsync — a lightweight app that did one thing: sync Nightscout data (glucose, insulin, carbs) to Apple Health. No frills, no dashboard, just a bridge. That was enough for a while.

Then came the wearables

Once the glucose data was in Apple Health, the next question was obvious — what about sleep? HRV? Recovery? The Oura Ring had all of it, but it was locked away in its own silo. So Oura integration came next: sleep stages, HRV, SpO2, heart rate, temperature — all synced to Apple Health without needing a subscription.

One app for all of it

With glucose, insulin, and wearable data all in one place, the full picture finally made sense. daatlas grew into a proper app — dashboard, trends, budget tracking, Dexcom support — built on top of the same bridge that started it all.

daatlas-healthsync still exists as a standalone app for anyone who just wants the simple Nightscout sync without the rest.

At a Glance

How it works

Nightscout  ──┐

Dexcom      ──┼──►  daatlas  ──►  Apple Health  ──►  Any app in the ecosystem

Oura Ring   ──┘

Once synced, your data lives in Apple Health — available to every app in the ecosystem. daatlas is just the bridge.

Key Features

• 
  Glucose sync — Nightscout SGVs or Dexcom Share readings in mg/dL or mmol/L


• 
  Insulin tracking — Bolus and basal deliveries mapped to HealthKit insulin types


• 
  Oura sync — Sleep, HRV, readiness, SpO2, heart rate, temperature (no Oura subscription needed)


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  Deduplication — Never writes the same record twice (Nightscout _id + timestamp fallback)


• 
  Background sync — Configurable intervals from 5 minutes to 2 hours


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  Sync logs — Full audit trail of every sync operation


• 
  Live Activities — Glucose on Dynamic Island and Lock Screen


• 
  Claude export — Export a date-range data dump for AI analysis

Integrations

Why open source

Diabetes tooling should be free. The data belongs to you. daatlas builds on top of the incredible open-source diabetes community — Nightscout, Cracked-Oura, tconnectsync — and gives back under GPL v3.

Tech Stack

iOS 16+ · SwiftUI · HealthKit · Swift async/await · Actor concurrency · XcodeGen

The entire service layer is built with Swift actor types — compile-time thread safety, no manual locking, no data races. HealthKitService is the single write path to Apple Health.

What's next

• 
  Live Activity improvements — real-time glucose on Dynamic Island with trend arrows and time-in-range


• 
  Food logging — AI-assisted carb estimation from photos, barcode scanning, meal history


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  Apple Watch app — quick sync status, glucose glance, complication support


• 
  Shortcuts & automation — Siri Shortcuts, glucose-triggered automations


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  VO2 Max sync — Oura VO2 Max to HealthKit


• 
  Widget — home screen glucose + sleep score + HRV


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  CSV / PDF export — data dump for clinic visits


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  iCloud sync — settings and sync history across devices

Known Limitations

• 
  Oura without membership requires manual export — no real-time background sync; re-export needed for new data


• 
  No offline sync — all syncs require network connectivity


• iOS 16+ only

Great apps in the diabetes space

Gluroo — a beautifully designed diabetes management app. If you want a polished all-in-one experience, check it out.

Stash Diabetes — great app for managing and tracking diabetes supplies. Highly recommended.

xDrip4iOS — open-source CGM reader for iOS. Supports a wide range of sensors and is the go-to for DIY CGM setups.

Acknowledgements

• 
  Cracked-Oura — reverse-engineered Oura API access without a subscription


• 
  tconnectsync-heroku — Tandem pump data bridge to Nightscout


• 
  Nightscout — the open-source diabetes platform that makes all of this possible

daatlas is not a medical device. It is a data utility for personal use. Always consult your healthcare provider for diabetes management decisions.

View source on GitHub →