Heart And Vitals

Status: Current implemented behavior. One parametric screen serves all ten metrics. Audience: Users and contributors. Implementation: features/heart, features/vitals, features/manualentry/vitals, data/repository/HeartRepository.kt, data/repository/VitalsRepository.kt. Navigation: Screen.Metric, vitals entry routes; heart and vitals dashboard widgets. Related: Feature map, Manual entry of metrics, Statistics.

Heart and vitals are related but distinct feature areas, and the split is in the data layer, not the screen layer.

• features/heart owns heart-rate-oriented state, presentation mapping, and route wrappers for average heart rate, resting heart rate, and HRV.
• features/vitals owns vitals-facing screens and UI helpers such as blood pressure, SpO2, VO2 max, respiratory rate, body temperature, blood glucose, skin temperature, and the Today Vitals overview.
• The read split is real: HeartRepository serves heart rate / resting heart rate / HRV, VitalsRepository serves the rest, and LoadHeartPeriodUseCase combines them so one screen can load either family.

The current implementation still shares HeartViewModel and the heart period loader across heart and vitals routes. That is an intentional transitional boundary: the user-facing vitals UI lives in features/vitals, while some loading and state infrastructure remains shared until a deeper split is worth the extra complexity.

Implemented Metrics

Heart metrics:

• Average heart rate.
• Resting heart rate.
• HRV.

Vitals metrics:

• Blood pressure.
• SpO2.
• VO2 max.
• Respiratory rate.
• Body temperature.
• Blood glucose.
• Skin temperature.

Skin Temperature

Health Connect stores skin temperature as a variation: how far your skin moved from a baseline the device set, not a temperature you could read off a thermometer. A record may or may not carry that baseline, and it can span hours with a sample every minute. The skin temperature screen reads it that way:

• Every value is a variation in signed degrees, under “Variation from baseline”. OpenVitals never adds the baseline back to make up an absolute temperature.
• Charts are centred on zero, with a dashed zero line. The day view draws the samples through the day instead of one dot at the end of the record.
• Comparisons are in signed degrees, not a percent of a small number (which used to print things like “-652 % vs previous day”). Your personal baseline keeps the days below zero, and the tile that compares with it is called “Vs usual average”.
• The device’s own baseline has a “Baseline” tile: the one the period’s records share, or the newest one, marked “From the newest record”, when they differ. It says “Not provided by source” when no record has one.
• A record with no samples reads “No variation recorded”; its baseline is never shown as a reading. The dashboard tile shows the newest record that has a variation.

Detail Pattern

Heart and vitals detail screens use the shared metric detail scaffold:

• Day, week, month, and year ranges.
• Selected anchor date.
• Previous/next period navigation.
• Calendar date picking.
• Pull to refresh.
• Intraday charts where sample data is available.
• Period charts, statistics, thresholds, comparisons, data confidence, source labels, and entry lists.
• Reorderable sections.

OpenVitals-created vitals entries can be edited or deleted when the app has write permission and ownership can be verified, blood glucose and VO2 max included. External records stay read-only. Blood glucose and VO2 max can be entered from Add entry since 2.15.0, see Manual entry of metrics.

Blood Pressure Categories

The latest reading is named with the categories of one guideline. Settings, Vitals holds the choice: ACC/AHA 2017 (the default), ESH 2023, ESC 2024, or ISH 2020. ACC/AHA counts 130/80 mmHg as high; the other three count 140/90.

• A reading takes the highest category that either number reaches.
• Every guideline flags a reading above 180 systolic or above 120 diastolic.
• The “How it is classified” card on the blood pressure screen names the guideline, lists its thresholds, and links its sources.
• The thresholds are for adult readings taken in a clinic. Home readings often run lower.

Today Vitals

Each heart and vitals dashboard tile opens its own focused metric screen directly - tapping Blood pressure opens the blood pressure detail, not an intermediate overview.

Data Boundaries

Heart-rate and vitals records are read through feature-facing repository/use-case APIs rather than a global browser. Manual vitals entry lives under features/manualentry/vitals. Dashboard heart and vitals tiles open their per-metric screens directly.