PhyOSC vs Heart Matter
Price, ratings, monetisation and update history for both apps, side by side — with what reviewers say about each.
PhyOSC
This app uses Apple Watch data to control sound based on your body movements. It converts sensor data and arm movements into OSC messages for DAWs, allowing for dynamic soundscapes during exercise. Customize filters and settings for varied audio expressions.
- Receives Core Motion data from Apple Watch
- Converts sensor data to OSC messages
- Supports 12 types of arm movements
- Applies digital filters to data
- Saves and recalls filtered settings
- Switches DAW devices via settings
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PhyOSC is an application that supports your exercise with Apple Watch, controlling the sound according to your body movement. Instead of uniform music at the sports gym, The instructor's improvisational movement enhances the atmosphere of the venue during the session. ------------------------- Features of PhyOSC ------------------------- 1) PhyOSC receives Core Motion data from Apple Watch on iPhone. The iPhone converts this sensor data and 12 types of arm movements trained by machine learning into OSC messages and sends them to the IP address and Port number to which the DAW is connected. 2) PhyOSC can apply a digital filter when converting Apple Watch Core Motion data received by iPhone into OSC message data. 3) OSC can name and save the filtered settings. This setting can be instantly recalled and switched, so even with the same arm movement, setting A produces a cheering sound effect, and switching to setting B produces a drum kick sound. It realizes a variety of expressions such as changing the waveform of the oscillator and the oscillator. In addition, the TCP / IP address and Port number of the OSC message destination are set in the settings, so you can switch DAW devices by switching the settings. ------------------------- System Requirements ------------------------- PhyOSC requires iPhone and Apple Watch. The required operating environment is as follows: Apple Watch : watchOS 8 Apple Watch Series 5 or higher recommended iPhone: iOS 15 iPhone 8 or higher recommended ------------------------- Limitations ------------------------- The accuracy of machine learning recognition is not 100%. Incorrect results may be output depending on the speed and angle of arm movement. We continue to research the latest research and look for new approaches to improve accuracy.
Heart Matter
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Tracks real-time heart rate with most BLE chest strap heart rate sensors. Some smartwatches and wrist-worn devices may not connect because they do not support the standard BLE Heart Rate profile. Whether you’re aiming for fitness or endurance, effective aerobic exercise means keeping your heart rate at 60–80% of your maximum for at least 15 minutes. Simply set your age, and the app automatically calculates your maximum heart rate and key target zones (60%, 70%, 80%), then shows them on a real-time graph—helping you avoid slowing down or pushing too hard, for safer, more effective workouts. When you press the PiP button, a small window appears. The color on the left side of the window indicates system status: green means normal, red indicates overheating, and gray shows delay. The blinking dot next to the number confirms that heart rate is being measured and updated continuously. The background color of the number on the right side represents heart rate zones: below 60% of maximum is blue, up to 80% is green, up to 90% is orange, and above 90% is red. Features: • Real-time heart rate and RR interval tracking with most BLE chest-strap monitors (smartwatches and wrist devices not supported) • Continuous background heart rate collection—even with the screen off • Automatic reconnection to your last paired device, with alerts if the connection drops • Full connection event logging for reliable monitoring • Customizable high heart rate alerts • Seamless data sync with Apple Health
Screenshots
Verdict
The clearest difference is in-app purchases: Heart Matter at none against PhyOSC's 1. Heart Matter also leads on update cadence (every 5 weeks vs every 7 months). On price, ads, device support and iOS requirement there is nothing between them.
Scored on Price · Rating · Positive reviews · Number of ratings · Update frequency · Ads · In-app purchases · Monetization · Best chart rank · Devices · Requires iOS
Both are free to download. PhyOSC sells 1 one-off in-app purchase. Heart Matter asks for nothing beyond the download.
PhyOSC ships an update every 7 months, Heart Matter every 5 weeks. The most recent releases landed on September 22, 2026 and October 3, 2026 respectively.
| Parameter | PhyOSC | Heart Matter |
|---|---|---|
| Price | Free | Free |
| Rating | 3.0 (2 ratings) — better | — |
| Positive reviews | 0.0% of reviews | — |
| Number of ratings | 2 — better | — |
| Update frequency | Every 7 months | Every 5 weeks — better |
| Ads | No | No |
| In-app purchases | Yes | No — better |
| Monetization | Free | — |
| Devices | iPhone, Apple Watch | iPhone, iPad |
| Requires iOS | 16.6 — better | 17.6 |
| Further details — not scored | ||
| Size | 9 MB | 5 MB |
| Age rating | 4+ | 4+ |
| Developer | Masaru Suzuki | ILHYUN KOH |
In-app purchases
PhyOSC
- Unlimited$0.99
Heart Matter
No in-app purchases









