Going Deeper: Stages, Biometrics & Trends

Set up for good stage data

Sleep stages in Snore Timeline come from sound. The app listens to your breathing rhythm, how regular it is, and your movement, then estimates whether you're in Light, Deep, or REM sleep, or Awake. Steady, metronome-like breathing points to Deep sleep, moderate regularity to Light, and more irregular breathing to REM. Since the whole estimate rides on hearing your breath, your setup decides how good the data is.

A few things give the estimator the clearest signal:

1. Close placement. Keep the phone about 1 to 2 feet from your head. Breathing fades fast with distance, and faint breathing is what stages depend on. The full reasoning is in Getting Started.
2. A quiet room. Fans, white noise machines, air purifiers, HVAC, and a TV left on cover up the breathing the app needs. When breathing drops below what the app can make out, that stretch reads as Silence instead of a stage. Silence still counts as restful sleep, but you lose the stage detail for that window.
3. A consistent baseline. The app works out your personal breathing baseline, your typical rate and regularity, during the first part of the recording, then measures the rest of the night against it. Respiratory rate settles after roughly the first 10 to 15 minutes of detected sleep. Record the same way each night so that baseline stays comparable across your trend.

Longer recordings sharpen the estimate, since several hours give the app more complete sleep cycles to look at. How each signal maps to a stage is covered in Sleep Stages, and the hypnogram section explains how to read the stage chart.

Connect your watch and Health

An Apple Watch adds a second, sensor-based view that audio can't reach. When a watch reports sleep-stage data for the night, Snore Timeline uses the watch's Deep and REM percentages for your sleep score in place of its own audio estimates, since a wrist sensor measures those stages more accurately. Without a watch, the app falls back to its breathing and movement estimates.

A paired watch also adds biometrics to your summary and your export:

• Heart rate, including average, minimum, maximum, and a resting estimate.
• Heart rate variability (HRV).
• Blood oxygen (SpO2). With watch SpO2 data, the app can show the percentage of the night spent below 95% oxygen saturation and your lowest reading.
• Respiratory rate from the watch, alongside the app's own audio estimate.
• Wrist temperature, which appears in the per-night aggregates.

All of this comes through Apple Health. Snore Timeline reads watch biometrics from Health, and it works fully with microphone access alone, so the watch is an extra and never a requirement. Health and other permissions only come up when you turn those features on. Setup steps, the full biometrics list, and notes on other wearables are in Apple Watch & Biometrics, with details on the data exchange in the Apple Health and other wearables sections.

Read the full picture

One signal on its own tells you very little. The value comes from reading them together for a single night, then doing that night after night. Work through the summary in this order:

1. Start with the hypnogram. Get the shape of the night. When Deep clustered, when REM built toward morning, where you woke. Snore Timeline treats Deep sleep around 13 to 23 percent of your sleep and REM around 20 to 25 percent as general guidelines.
2. Lay snoring and disruptions over it. Open the episode list and note when the loud stretches landed. Did heavy snoring line up with lighter stages, or with a cluster of breathing disruptions? The timeline lets you jump to any moment and play it back. See Timeline & Playback.
3. Add the biometrics. Check whether your watch SpO2 dipped during the same window, or whether heart rate stayed high through a noisy stretch. These are correlations to notice. They don't prove a cause.
4. Read the sleep score last. The 0 to 100 score rolls all of this into one number. Duration carries the most weight, with 7 or more hours treated as ideal. Deep and REM percentages, efficiency, time to fall asleep, awakenings, bedtime consistency, snoring, and breathing disruptions all feed in too. Tap the score badge for a factor-by-factor breakdown. The Sleep Score page explains each input.

Snore Timeline also keeps a Sleep Bank against your nightly sleep goal, 7 hours unless you change it, so you can see sleep debt building up instead of judging one night. Pair that with the weekly trends view and your sleep deficit to read the direction over time instead of reacting to one rough night.

Analyze trends in a spreadsheet

The in-app trends answer most questions, but a spreadsheet lets you chart your own metrics and join nights to anything you track outside the app. Snore Timeline exports your data as CSV files bundled in one ZIP. Build the export like this:

1. Open the export screen and pick a date range. Last 7 days, Last 30 days, or All time. For trend work, choose All time and filter inside the spreadsheet.
2. Choose the categories you want. Each one becomes its own CSV. Nightly Summary (one row per night), Sleep Stages (stages over time from phone and watch), Detected Events (snoring, sleep talking, coughs, gasps, breathing disruptions), and Watch Biometrics.
3. Generate the report, then tap Share Export to send the ZIP by email, Messages, AirDrop, or into a cloud drive. The files open in Numbers, Excel, or Google Sheets.

For charting trends across many nights, the Nightly Summary CSV is your main table. It has one row per night, with columns including Night, Sleep Score, Sleep Efficiency, Total Sleep (s), Time to Sleep (s), Light Sleep (s), Deep Sleep (s), REM Sleep (s), Silence (s), Awake (s), WASO (s), Awakenings, Avg Respiratory Rate (bpm), Episode Count, Loudest Peak (dB), Average Peak (dB), Total Snore Signals, Total Gasp Events, Total Cough Events, Total Sleep Talking Events, and Total Breathing Disruptions. Durations are in seconds, so divide by 3600 to chart hours.

The supporting files let you go finer-grained:

• Sleep Stages CSV has Night, Source, Stage, Start Time, End Time, Duration (s), Reason, and Breathing Rate (bpm). Source tells you whether a stage came from Snore Timeline or a watch, so you can compare the two.
• Detected Events CSV has Type, Timestamp, End Time, Peak dB, Source, Silence Start, Silence Duration (s), and Recovery Strength (dB). The silence and recovery columns fill in for breathing disruptions.
• Watch Biometrics ships as two files: a Samples file of individual readings (Night, Source, Metric, Timestamp, Value, Unit) and an Aggregates file with per-night summaries of heart rate, HRV, SpO2, respiratory rate, and wrist temperature.

Timestamps are ISO 8601 with timezone (for example 2024-01-15T22:30:45-08:00) and night identifiers are plain YYYY-MM-DD dates, which sort and filter cleanly. To chart a trend, put Night on the x-axis and the metric you care about on the y-axis. Sleep Score over 90 days, Total Breathing Disruptions per week, or Deep Sleep as a percentage of Total Sleep. The full column reference and audio-bundling options are in Export & Sharing, and the export report section covers building the file.

The limits

Read across nights. A single rough reading often comes down to a noisy room or a phone too far away, and says nothing about your sleep. The trend is what carries the signal. The accuracy notes for stages and the guidance on when stages don't appear are worth reading before you lean on any one figure.