NoctO₂
About

Peace of mind for the night, made simple

NoctO₂ is a small, independent app. It’s free, it has no ads, and it’s built around one idea: your oximeter already knows when something’s off at night, so your phone should tell you, and if you want, the people who care about you.

Why NoctO₂

Built because the night is when it matters

Sleep oximeters are affordable and good at measuring, but their own alarms are easy to sleep through, and their apps are mostly for looking back the next morning.

NoctO₂ watches the readings live, all night, with alarms you set yourself. If an alarm goes unanswered, it can tell your family. And it does that without accounts, ads or collecting your data.

It’s made by one developer, in spare time, and shaped by the people who use it. If something would make it better for you, please say so.

NoctO₂ app icon

NoctO₂ at a glance

  • Free, with no ads or in-app purchases
  • No account, no tracking, no analytics
  • Readings stay on your iPhone
  • Optional family alerts, joined with a code
  • 7 supported oximeters, and counting
  • iPhone, iOS 16.4 or later
Good to be clear

What NoctO₂ is, and isn’t

✓ NoctO₂ is

  • A monitoring aid for your own consumer oximeter
  • Alarms based on limits you choose
  • A history of your nights, kept on your phone
  • A way to let family know when an alarm isn’t answered

✕ NoctO₂ isn’t

  • A medical device, or a diagnosis of any condition
  • A replacement for medical care or a medical alarm
  • An emergency service: in an emergency, call your local emergency number
  • Affiliated with Wellue/Viatom, Lepu-Creative or EMAY
Contact & feedback

We read every message

Questions, bugs, a device you’d like supported, or an idea that would make NoctO₂ better: send it here.

Email

ngc1348@gmail.com

For problems, please include your iPhone model, your oximeter model and what happened. The troubleshooting log (Settings → Diagnostics → Share) helps a lot.

Before you write

Most questions are answered on the Support page, with pictures. Family questions are on the Family page.

What is it about?

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