Launching Calometric: A Nutrition Tracker That Respects Your Privacy

I’ve never been great at tracking what I eat. I’d download a calorie tracker, spend five minutes manually searching for “grilled chicken breast 150g,” give up after three days, and delete the app. The friction was always too high.

Most nutrition apps want you to weigh everything, type everything, and subscribe to everything. And in return, they collect your data and sell it to advertisers. That never sat well with me.

So I built something different.

Introducing Calometric

Calometric is a nutrition tracker for iPhone and Apple Watch. Take a photo of your meal, and it tells you the calories and macros. That’s the core idea.

What makes it different is where the AI runs: entirely on your device. The food recognition uses Core ML, and the portion estimation uses Apple’s Foundation Models. Nothing gets sent to a server. There’s no account to create. No data to leak.

Five Ways to Log

Not every meal is a photo opportunity. Sometimes you’re eating a protein bar with a barcode. Sometimes you’re driving and just want to say “two eggs and toast.” So I built five input methods:

• Photo scan for when you can snap a picture
• Barcode scanner for packaged foods (via Open Food Facts)
• Voice logging for hands-free moments
• Food search against a local USDA database with 177+ foods
• Nutrition label OCR for when you want exact numbers from the package

Each one feeds into the same pipeline and saves consistently to SwiftData, HealthKit, Spotlight, and widgets.

Why On-Device AI?

Privacy was a hard requirement from day one. I didn’t want to build something that phones home every time you eat lunch. But beyond privacy, there’s a practical benefit: it works offline. On a plane, in the mountains, in your kitchen with spotty Wi-Fi. It just works.

The trade-off is that on-device models aren’t as powerful as cloud models. The AI portion estimation requires an iPhone 15 Pro or newer with Apple Intelligence enabled. On older devices, everything still works, you just get default portion sizes instead of smart estimates.

Apple Watch Too

I wanted to log meals from my wrist. The watchOS app is fully independent, with voice logging, a quick-add menu of common foods, and complication widgets showing your daily progress. It syncs with the iPhone via WatchConnectivity.

The Business Model

One-time purchase. That’s it. No subscriptions, no ads, no in-app purchases. One price covers iPhone and Apple Watch.

I keep coming back to this model because I believe in it. If you’re building a tool that respects people’s privacy, charging them a recurring fee to keep accessing their own data feels contradictory.

Try It

If you’re looking for a nutrition tracker that stays out of your way and keeps your data on your device, give Calometric a look.

Download on the App Store | Website