SyncZero - Capture Monitor

Sometimes you do not need another display. You just need a focused way to preview HDMI on the device you already use.

SyncZero is a lightweight USB capture card monitor for macOS and iPadOS. Connect a UVC-compatible USB capture card to preview video from game consoles, cameras, computers, or other HDMI sources, with audio input from the capture card when supported.

It is built for people who want a cleaner portable setup: connect a console in a dorm room, check another device on your desk, or monitor camera output in the field. Open the app, choose a capture device, and enter a focused preview experience.

SyncZero uses native capture APIs, audio input, and a Metal rendering pipeline, with attention to responsiveness, clarity, and practical image controls. On supported hardware and capture cards, it provides a smooth real-time audio and video preview with enough tuning options for different sources.

Key features:

HDMI preview on macOS and iPadOS

Preview external HDMI video through a USB capture card, with audio input from the capture card when your system exposes it.

Low-latency experience for play and monitoring

Reduce unnecessary display overhead for a more responsive preview, useful for console gameplay, camera monitoring, and desktop setups.

Synchronized audio capture

Receive audio input from the capture card, so games, monitoring, and device previews can be seen and heard.

Resolution switching

View supported formats from your capture device and switch resolutions during playback.

Actual output at a glance

See both negotiated and actual output resolution to better understand what your capture card and system are providing.

Aspect and rotation controls

Choose Fill, 16:9, or 4:3 display modes, and rotate the image when needed.

One-tap image presets

Built-in presets include Game, Office, Cinema, and FPS. You can also adjust brightness, contrast, saturation, and sharpening manually.

Advanced image settings

Fine-tune sampling and color modes for different capture cards, displays, and content types.

Settings remembered per device

SyncZero remembers resolution and image settings for each capture device, so your preferred setup is ready when you reconnect.

Use cases:

Preview game console video through a capture card

Portable HDMI monitoring on the go

Monitor camera output through a capture card

Reduce the need for an extra display in desk or mobile setups

Requirements:

macOS 14.0 or later

iPadOS 17.0 or later

A UVC-compatible USB capture card

USB 3.0 or later capture devices and cables are recommended

Audio input, resolution, and frame rate support depend on the capture card, source device, and system environment

On iPadOS, capture card audio depends on whether the system exposes the device as an available USB audio input. Some capture cards may support video preview only and may not provide capture card audio.

Privacy:

SyncZero requests camera permission to access USB video capture devices and microphone permission to receive capture card audio. The app does not upload, store, or share your captured video or audio content.