Privacy policy
Stress Radar is an iPhone app that compares your heart rate and heart rate variability with your calendar and with the Bluetooth devices around you. This page explains what it reads, what it keeps and where. The short version: everything stays on your phone, and the app has no way to send it anywhere.
What the app reads
- Health
- Heart rate, heart rate variability (SDNN), workouts, sleep analysis and mindfulness sessions, read through HealthKit. Workouts, sleep and mindfulness are only used to decide which readings to leave out. The app never writes to Health.
- Calendar
- Event titles, times, calendar names, attendee names and locations, read through EventKit for the look-back window you choose (7 to 90 days). The app never changes your calendar.
- Bluetooth
- The advertised name, identifier, signal strength and service identifiers of nearby Bluetooth Low Energy devices, while scanning is on. Devices without a name are ignored unless you opt in.
- Notifications
- Permission to show one local notification a week, if you turn the weekly summary on.
What the app stores, and where
Bluetooth sightings and the labels you give devices are stored in a database inside the app's private container on your phone, and are backed up with the rest of your phone. A copy of the heart readings and calendar events used by the last analysis is cached in the same container so the app can open quickly; that cache is encrypted with your passcode and excluded from iCloud and computer backups, as Apple requires for Health data. The widget reads a small summary (your index, an event title and, if you allow it, the label of a device in range) from a container shared only between the app and its widget. That summary is excluded from backups too.
What leaves your phone
Nothing, unless you choose to share it. The app contains no networking code, no analytics, no crash reporting service and no advertising. Its privacy manifest declares no tracking and no collected data. The CSV export puts files in the iOS share sheet; where they go from there is your decision.
Other people
Attendee names come from your own calendar and device labels are ones you typed. They are shown only inside the app and, if you allow it, on your home-screen widget. The weekly notification and the lock-screen widget never name a person or a device.
Deleting your data
"Clear device history" in Settings removes all recorded sightings and labels. Deleting the app removes everything, including the cache and the widget summary. The app never writes to Health or to your calendar, so there is nothing to undo there.
Changes and contact
If a future version changes any of this, the change will be described here with a new date before that version ships. Questions go to contact@stress-radar.io.