Saturate – Effective O₂
Oxygen in the air around you
Only for Watch
Free
Apple Watch
The higher you go, the less oxygen every breath delivers. See live effective oxygen, altitude, and pressure — on your wrist and right on your watch face.
At 10,000 feet, every breath you take delivers about 30% less oxygen than at sea level. Saturate turns your Apple Watch into a live oxygen meter for the air around you — so you can see exactly what you're breathing while you climb, ski, hike, or fly.
Using the barometer on your wrist, Saturate measures the actual air pressure around you and converts it into "effective oxygen": the sea-level equivalent of what each breath delivers right now. At the beach, that's 20.9%. In Denver, about 17%. On a 14,000-foot summit, closer to 12%.
WHAT YOU SEE
• Effective oxygen % — the headline number on a color-coded ring
• % of sea-level oxygen — 100% at the beach, falling as you climb
• Six altitude zones, from Low (green) to Ultra (indigo)
• A live altitude scale from sea level to 29,000 ft, with a marker for where you stand
• Your current altitude, air pressure, and nearby place name
• A trend arrow that shows whether your air is getting richer or thinner
ON YOUR WATCH FACE
Three complication styles for any face: a rectangular overview with oxygen, altitude, and % of sea level at a glance, plus focused Effective O₂ and % of Sea Level gauges for circular, corner, and inline slots. They quietly keep themselves fresh through the day.
BUILT FOR THE WRIST
• Watch-only — nothing to install on your iPhone, nothing extra to carry up the mountain
• Steady by design — readings are smoothed so the number locks in instead of flickering
• Feet or meters, with an optional extra decimal of precision
• Falls back to GPS altitude on watches without a barometer
PRIVATE BY DESIGN
No account. No ads. No analytics. No developer servers. Every reading is computed on your watch, from your watch. If you enable location, Apple's geocoding service may be used to show a nearby place name — that's it.
GREAT FOR
• Hikers, climbers, mountaineers, and trail runners
• Skiers and snowboarders
• Altitude training and acclimatization awareness
• Travelers to high-altitude cities
• Frequent flyers — watch the cabin "climb" to 7,000 feet
• Anyone curious about the invisible air around them
NOT A MEDICAL DEVICE
Saturate measures the surrounding air — not your blood oxygen (SpO₂). It does not diagnose, treat, or provide medical advice. Always follow proper acclimatization guidance at altitude.
Ratings & Reviews
The developer, Jacob DeNelsky, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- Jacob DeNelsky
- Size
- 1.8 MB
- Category
- Weather
- Compatibility
Requires iOS 13.0 or later.
- iPhone
Requires iOS 13.0 or later. - iPod touch
Requires iOS 13.0 or later. - Apple Watch
Requires watchOS 10.0 or later.
- iPhone
- Languages
- English
- Age Rating
4+
- 4+
- Copyright
- © 2026 Sapphire Prism Labs
