Coherence App
HRV Biofeedback & Breathwork
$3.99
Stop guessing recovery. Just breathe and observe your body improve through ITFD-guided breathing, HRV analysis, and clearer autonomic insight.
Coherence is a structured physiological evaluation app built around Heart Rate Variability (HRV) and guided breathing sessions.
It does not measure relaxation.
It evaluates autonomic behavior, cardiac coherence and recovery patterns through structured session analysis.
HOW SESSIONS WORK
Sessions are started from Apple Watch. Breathing is guided using haptic feedback and color cues:
• Haptic + blue = nasal inhalation
• No haptic + green = nasal exhalation
Inhalation timing is detected algorithmically in real time. The ITFD algorithm continuously evaluates HRV dynamics and determines the optimal breathing rate and inhalation–exhalation structure during the session.
Signal acquisition is performed through Apple Watch. When available, external chest straps such as Movesense or Polar H10 can be used to refine HRV signal quality and improve algorithmic precision.
If the HUM button is blinking before starting, the ITFD algorithm has detected that adding humming during exhalation is recommended.
Humming is performed as Single-Breath Humming: a steady low sound during the entire exhale, producing stable nasal vibration. This vibratory nasal exhalation is associated with nitric oxide (NO) release. For more detailed information, see the corresponding sections in the Features area of our site.
To avoid consciously forced diaphragmatic breathing, the app proposes a light index–thumb opposition as a sensorimotor anchor. This subtle gesture supports postural stability and reduces accessory respiratory engagement without deliberate control. For more detailed information, see the corresponding sections in the Features area of our site.
MEASUREMENT AND INTERPRETATION
Each session generates an ITFD score derived from HRV behavior across repeated sessions. The model integrates SDNN and RMSSD dynamics to provide structured physiological interpretation.
The main card displays, by default, the latest recorded session. If a specific day is selected in the calendar, the card reflects the results of that selected session instead.
The dynamic background and main card interface include real-time graphical responses to physiological data during the session. Visual intensity and motion adapt continuously to coherence and stress dynamics, functioning as structured biofeedback rather than decorative animation.
The main card includes:
• A 7-day mini-chart showing daily minimum and maximum ITFD values
• Directional change compared to the previous session
• An interpretive phrase integrating structural analysis and circadian context
• A selectable calendar
• A 30-day trend summarizing overall progression
The interpretive phrase reflects the session within the system’s daily pattern, not only an isolated change.
In addition to the main interpretation, each session includes detailed charts displaying stress, coherence, and heart rate (HR) data. These charts provide structured visual feedback and allow observation of session dynamics both in real time and retrospectively.
STRUCTURE
The app is ideally designed for one session in the morning and one in the evening to evaluate daily autonomic patterning. Early sessions progressively stabilize as more data is recorded.
Coherence does not provide generic stress scores, motivational framing, or lifestyle coaching.
It is designed for users interested in structured HRV interpretation, cardiac coherence analysis, and measurable autonomic dynamics.
- This app’s overall rating was recently reset.
This build fixes an issue detected in the initial permission-grant flow, preventing certain calculations from running before the authorization state was fully resolved. It also strengthens permission handling to make app startup more robust and consistent.
The developer, TICTACTEL, indicated that the app’s privacy practices may include handling of data as described below. For more information, see the developer’s privacy policy .
Data Not Collected
The developer does not collect any data from this app.
Accessibility
The developer has not yet indicated which accessibility features this app supports. Learn More
Information
- Seller
- Gomez Martinez Felipe
- Size
- 15.7 MB
- Category
- Health & Fitness
- Compatibility
Requires iOS 18.6 or later.
- iPhone
Requires iOS 18.6 or later. - Apple Watch
Requires watchOS 10.5 or later.
- iPhone
- Languages
- English and Spanish
- Age Rating
9+
- 9+
- Contains
Health or Wellness Topics
- Copyright
- © 2026 Coherence App

