Privacy Policy

SynthBridge KeyCaster · Last updated: April 18, 2026

Overview

SynthBridge KeyCaster ("the App") is developed by Novaryn as part of the SynthBridge product series. The App turns a Bluetooth or USB keyboard into a virtual MIDI controller. This policy explains how the App handles your data. It is deliberately short because the App is designed to handle as little data as possible.

Data Collection

We do not collect, store, transmit, or share any personal data.

• No account or sign-up is required.
• No analytics, telemetry, or tracking SDKs are integrated.
• No advertising networks are used.
• No crash reports are sent automatically.

Data Stored Locally on Your Device

The App stores the following data only on your device:

• Custom presets — the MIDI mappings you create, edit, duplicate, or import (stored in Room / SQLite).
• Settings — your active preset, default MIDI channel, default velocity, global velocity slider value, and onboarding-completion flag (stored in Android DataStore).

This data never leaves your device unless you explicitly export a preset via the system file picker.

Hardware Access

The App accesses the following hardware for its core function:

• Bluetooth / USB input keyboard — Android routes key events to the App via the standard HID pipeline; we do not pair, discover, or read any other Bluetooth / USB data.
• MIDI framework — the App registers as a virtual MIDI output device using android.media.midi.MidiDeviceService. Other MIDI-capable apps on the same device may read the MIDI stream we produce (this is the entire purpose of the App).

Permissions Requested

• BIND_MIDI_DEVICE_SERVICE — expose a virtual MIDI source to the system (required).
• FOREGROUND_SERVICE / FOREGROUND_SERVICE_SPECIAL_USE — keep the preset-switch notification alive while the App is in the background.
• POST_NOTIFICATIONS (Android 13+) — show the preset-switch notification.
• Accessibility Service — continue reading the hardware keyboard while another app is in the foreground. Fully optional; the App works without it.

No other runtime permissions are requested.

The Accessibility Service

When the user manually enables the KeyCaster Global Capture accessibility service, the App receives key events from the system while other apps are in the foreground. These key events are:

• Used only to produce MIDI messages on the virtual MIDI device this App publishes.
• Never logged, stored, or transmitted off-device.
• Never inspected for character content — only the raw keyCode (e.g. KEYCODE_A) is read.

The App does not read screen content, window titles, notifications, or any other accessibility data.

Third-Party Services

None. No analytics, advertising, or tracking SDKs are embedded.

Children's Privacy

The App does not target children specifically. It does not collect personal information from anyone regardless of age.

Changes to This Policy

If we ever change what data is handled, this policy will be updated and the new version will ship with the next App release. Material changes will be highlighted in the release notes.

Contact

Questions about this privacy policy can be sent to:

[email protected]