PulseO2: Blood Oxygen Tracker

Your Blood Oxygen. Back on your wrist.

Your Apple Watch measures your blood oxygen throughout the day and night. PulseO2 puts those readings where you can see them at a glance: on your watch face, in the app, and on your iPhone. In the US, where Blood Oxygen results appear only in the Health app on iPhone, PulseO2 brings every new reading back to your wrist automatically.

ONE PRICE. ONE TIME. EVERYTHING INCLUDED.
Buy PulseO2 once and every feature is yours. No subscriptions, no in-app purchases, no tip jars, no premium tier, and no ads. Every chart, every complication, every widget, and every future update is included.

ON YOUR WATCH FACE
• Circular, corner, and inline complications with your latest reading on a color-coded gauge
• A large complication with your choice of trend: 24 hours, 7 days, or 30 days
• Add more than one to see today and the past month side by side
• Readings dim once they're more than 4 hours old, so you always know how current they are

ON APPLE WATCH
• Your latest reading, last night, and the past 24 hours
• A 24-hour graph with today's average so far
• Today, yesterday, 7-day, and 30-day averages with time-in-range bars, plus a 7-day chart

WAKE UP TO LAST NIGHT
• Your overnight average and lowest reading
• How much of the night was below 95% and below 90%
• Uses your sleep times from Health, or 10 PM to 8 AM if you don't track sleep
• A morning notification sums up your night

SEE THE BIGGER PICTURE
• Trends for 24 hours, 7 days, 30 days, and 90 days
• Each day's average, low, and high, and how your average compares with the period before
• Day vs. night: your readings while asleep and awake, side by side
• Time in range: 95% and above, 90–94%, and below 90%
• Readings per day, and the times of day your watch measured

EVERY READING IN CONTEXT
• Tap any reading to see its level, where it fell within its day, and how it compares with readings taken around the same time on other days

LOW OXYGEN ALERTS
• Optional notifications when a reading falls below a level you choose

ON IPHONE
• Home Screen and Lock Screen widgets for your latest reading
• A 7-day trend widget in small and medium sizes
• Built-in questions and answers

AUTOMATIC
New readings reach your watch on their own. In the US, they're sent from your iPhone as it saves them to Health; iOS protects Health data while your iPhone is locked, so readings taken overnight reach your watch shortly after you unlock your iPhone in the morning.

PRIVATE BY DESIGN
No account. No ads. No tracking. PulseO2 makes no network connections. Your readings go only from your iPhone to your own Apple Watch.

REQUIREMENTS
• An Apple Watch that measures blood oxygen (Series 6 or later, or any Apple Watch Ultra), with Blood Oxygen set up in the Health app
• For readings while you sleep, turn on Blood Oxygen Measurements in the Watch app on iPhone (My Watch > Blood Oxygen)
• PulseO2 shows readings your Apple Watch has already taken. It can't start a measurement; use the Blood Oxygen app on Apple Watch for an on-demand reading.

PulseO2 is intended for general fitness and wellness purposes only. It is not a medical device and is not intended to diagnose, treat, or prevent any disease or condition.