Open Source Screen Video Capture on Mac: Kap vs OBS vs Shottr (and Where Reely Fits for App Launch Videos)

If you’re shipping iOS features fast, you’ve probably asked a version of this question:

What’s the best open source screen video capture tool on Mac for clean app demos – Kap, OBS, or Shottr?

For quick bug clips, any recorder will do. But for App Store previews, Product Hunt trailers, and launch videos, the choice matters.

This comparison breaks down Kap vs OBS vs Shottr on macOS, with a specific lens: mobile app launch videos and developer workflows. We’ll also show where Reely fits if you want to go from code → demo reel without hand-editing timelines.

TL;DR: Which tool should you use?

If you just want the quick answer:

• Kap – best lightweight, open source recorder for short clips and GIFs.
• OBS Studio – best open source option for full production control and longer app demo videos.
• Shottr – not a screen video recorder; it’s a screenshot/annotation tool.
• Reely – best fit if you want launch-ready iOS app promos generated from the iOS Simulator and your code, not a manual recorder.

For a broader overview of non‑open‑source options, see our related guide: “Best screen capture software for Mac: complete guide for indie app devs.”

Why open source screen recording isn’t the whole story for launch videos

Open source screen recorders give you:

• Cost control
• Transparency
• Flexibility and community plugins

But App Store previews and launch reels have their own constraints:

• Apple limits app previews to 15–30 seconds, with a 500 MB max file size and 30 fps cap.
• Footage must be captured on device (or simulator flows that mimic it) and macOS/tvOS/visionOS previews are landscape-only.
• Previews autoplay muted, so pacing and visual beats in the first seconds matter more than narration.

A recorder captures pixels. A launch video needs story, timing, kinetic type, and on‑brand design.

That’s the gap between tools like Kap/OBS and an app launch video generator like Reely.

The contenders at a glance

Here are the three tools developers most often compare when they search for “open source screen video capture on Mac”.

Kap

• What it is: An open source, menu‑bar screen recorder for macOS.
• Open source: Yes – 19.3k GitHub stars, 906 commits, latest release v3.6.0 (Oct 27, 2022).
• Exports: GIF, MP4, WebM, APNG; supports audio, click highlighting, and trimming.
• Workflow: Fire from the menu bar, record, trim, export. Plugin system for custom sharing.
• Best for: Quick app clips, GIFs, and lightweight demos.

OBS Studio

• What it is: A full broadcast/recording studio for desktop.
• Open source: Yes – 74.5k GitHub stars, 15,651 commits, latest Mac release 32.2.1 (Jul 24, 2026).
• Mac requirements: macOS 13+, separate Intel/Apple Silicon installers.
• Workflow: Scene‑based capture and compositing, multiple sources (simulator, webcam, browser), audio mixing.
• Best for: Longer app walkthroughs, layered overlays, multi‑source demos, and teams that need production control.

Shottr

• What it is: A screenshot and annotation app.
• Open source: No – proprietary license, free 30‑day trial, license required for commercial use.
• Key stats: Current version 1.9.1, tiny 2.3 MB DMG, 17 ms to capture, 165 ms to display.
• Important: Shottr’s own docs say it “never actually records the screen” – it is not a screen video recorder.
• Best for: Screenshots, OCR, scrolling capture, measurements, blur, and annotations to complement demos – not to replace video tools.

Feature comparison: Kap vs OBS vs Shottr (for app demo videos)

1. Open source status & licensing

• Kap – open source (MIT‑style); free, community‑driven.
• OBS – open source; widely adopted for streaming and recording.
• Shottr – not open source; commercial license needed for professional use.

If open source screen recorder on Mac is non‑negotiable, you’re looking at Kap vs OBS, not Shottr.

2. Performance & capture quality

Kap performance & quality

• Optimized for short captures.
• Uses standard macOS capture APIs; good enough for App Store resolution footage.
• Designed more for convenience than intense, hour‑long recording.

OBS performance & quality

• Designed for demanding recording and streaming.
• Supports ScreenCaptureKit-based capture on macOS 13+, including system audio where available.
• Performance depends on encoder, resolution, FPS, and scene complexity.
• Good choice for 1080p+ walkthroughs, multi‑window demos, or when you want more control over bitrate.

Shottr performance & quality

• Hyper‑optimized for screenshots – 17 ms to grab, 165 ms to display.
• No video pipeline at all.

For high‑quality, longer app demos, OBS wins. For short, non‑heavy clips, Kap is more than enough.

3. Ease of use for developers

Kap developer ergonomics

• Simple menu‑bar UI.
• Minimal config: pick a region/window, hit record, trim, export.
• Plugin system lets devs add custom export targets.
• Great for devs who want to capture a bug reproduction, small feature flow, or GIF quickly.

OBS developer ergonomics

• Powerful but not frictionless.
• Scene system, multiple sources, audio routing, profiles.
• Requires granting macOS permissions for Screen Recording, Camera, Microphone, and Accessibility.
• Has an Auto Configuration Wizard, but there’s still a learning curve.

Shottr developer ergonomics

• Ultra snappy for screenshots, measure overlays, and blur.
• Not relevant for video recording, but often lives in the same toolbox as Kap/OBS.

If your need is “record now, think later”, Kap is easier. If you want webcam + app + overlays + audio routing, OBS is worth the upfront setup.

4. Suitability for App Store previews & launch videos

Remember Apple’s key App Store app preview specs:

• Length: 15–30 seconds
• Max size: 500 MB
• Max frame rate: 30 fps
• Formats: .mov, .m4v, .mp4
• Orientation: macOS/tvOS/visionOS previews must be landscape

And Apple’s guidance: previews autoplay muted, so the first seconds must be visually compelling.

Kap for App Store previews

• Can capture clean simulator/device footage.
• No built‑in concept of pacing, beats, or titles.
• You’ll have to edit in a separate NLE (Final Cut, Resolve, etc.) to:
  • Trim to 15–30 seconds
  • Add titles/overlays
  • Match beats to music

OBS for App Store previews

• Lets you pre‑design a “scene” with:
  • Simulator window framed cleanly
  • Device frame overlay
  • On‑screen text or logo lower thirds
• Still requires post‑editing if you want tight pacing and kinetic type.
• Stronger for complex walkthroughs than concise, story‑driven 30s spots.

Shottr for App Store previews

• Useful to capture static frames or feature callouts.
• Cannot produce video; treat it as a companion screenshot tool.

Reely for App Store previews (where it differs)

• Built as an AI‑native app launch video generator for mobile developers.
• Lives as a native macOS editor that works with the iOS Simulator.
• Its agent/MCP tool can:
  • Recreate flows in the simulator
  • Record them
  • Auto‑cut dead air
  • Hand everything to a motion studio engine that stays fully editable
• Outputs 10–20s teasers and 30–60s launch promos tuned for App Store, Product Hunt, and social.

If your goal is “get a valid .mp4 from my screen”, Kap/OBS are enough. If your goal is “get a polished launch promo from my app flow”, that’s when Reely makes more sense.

Comparison table: Kap vs OBS vs Shottr vs Reely

Here’s a simplified matrix focused on indie dev needs.

Kap and OBS are the core open source recorders, while Shottr handles screenshots and Reely automates full launch promos.

| Tool | Open source | Primary use case | Best for indie devs who… | |--------|-------------|-----------------------------------------------|----------------------------------------------------------------| | Kap | Yes | Lightweight screen recording & GIF export | Want fast, simple clips without deep configuration | | OBS | Yes | Full‑featured recording/streaming studio | Need multi‑source, long demos and detailed control | | Shottr | No | Screenshots, OCR, annotation (no video) | Need pixel‑perfect screenshots, not motion | | Reely | No | AI‑generated app launch videos from flows | Want launch‑ready promos from simulator/code in minutes |

When Kap is the right choice

Kap shines as your everyday, low‑friction recorder:

Use Kap if:

• You’re capturing short bug reproductions for teammates.
• You need GIFs or quick MP4 snippets for X, Slack, or GitHub issues.
• You value an open source screen recorder that fits in the menu bar.
• You’re comfortable doing any serious launch edit in a separate NLE.

It’s also the cleanest benchmark for “fast path capture” in our broader Mac capture guide.

When OBS is the right choice

OBS is the power baseline: more complex, but far more capable.

Use OBS if:

• You need long-form app walkthroughs or tutorials.
• You want layered scenes (simulator + webcam + slides + overlays).
• You care about bitrate, encoder choice, and CPU headroom.
• You’re already familiar with streaming tools or willing to learn.

For many teams, OBS is the “build once, reuse forever” setup: dial in scenes for your app and reuse them across releases.

When Shottr belongs in your stack

Even though Shottr is not a video recorder, it is a strong companion:

Use Shottr if:

• You frequently need pixel-accurate UI screenshots.
• You annotate flows for design reviews or changelogs.
• You rely on OCR or scrolling capture for documentation.

Think of Shottr as your static visual tool, sitting alongside Kap/OBS or Reely.

When Reely is a better fit than manual recording

If you’re an indie iOS dev or small mobile team, your real bottleneck often isn’t:

“How do I record my screen?”

It’s:

“How do I ship a polished launch video without losing a day to editing?”

That’s where Reely is different from Kap, OBS, or Shottr.

Reely is an AI-native app launch video generator for mobile developers, built to integrate directly with your agent and simulator.

With Reely, you can:

• Describe the flow you want (or let your AI agent do it).
• Have the agent recreate the flow in the iOS Simulator and record it.
• Let Reely auto-cut dead air and build a reel with:
  • Kinetic typography systems
  • Device choreography presets
  • Music and sound cue timing
  • Editorial pacing tuned for App Store/Product Hunt style launches
• Output both:
  • 10–20s feature teasers
  • 30–60s full launch promos

Under the hood, Reely also:

• Runs as a native macOS editor with local rendering – no cloud uploads of your builds.
• Pulls a brand theme from your app so titles, backgrounds, and devices feel on‑brand.
• Keeps every scene fully editable, like a motion studio in a dev‑friendly wrapper.

If your agent can build the feature, Reely’s stance is: it should also build the demo reel.

Practical recommendations for mobile app launch videos

If you’re on a zero‑budget, open source–only stack:

• Use Kap for quick captures and OBS for serious walkthroughs.
• Expect to spend time in an NLE to craft real launch promos.

If you care more about speed than manual control:

• Use Reely to go from simulator flows to launch‑ready videos in minutes.
• Keep Kap or OBS around for edge cases (e.g., special hardware flows, live streams).

If you already use AI agents in your workflow:

• Connect Reely’s MCP/agent tool so your agent can go from:
  • “Build feature” → “Build demo reel” in the same workflow.

For most indie iOS devs, the best setup looks like:

• Kap or OBS for ad‑hoc capture.
• Shottr for screenshots.
• Reely for anything that needs to look like a launch, not a raw screen recording.

FAQ: Open source screen video capture on Mac for app demos

Is Shottr a good open source screen recorder for Mac?

No. Shottr is not a screen video recorder and it is not open source.

Shottr is a screenshot and annotation tool with features like OCR, measurements, blur, and scrolling capture. Its own documentation states it “never actually records the screen.”

Kap vs OBS for Mac: which should I pick for app demos?

• Choose Kap if you want a simple, open source menu‑bar recorder for short clips, GIFs, and quick MP4s.
• Choose OBS if you need longer, more complex demos with scenes, overlays, and fine‑grained control over resolution and bitrate.

Many developers install both and use Kap for quick tasks, OBS for “real” demo sessions.

Are Kap and OBS enough to create an App Store app preview?

Technically, yes – both can capture footage that meets Apple’s format and resolution requirements.

But to hit Apple’s 15–30 second length, 30 fps, and visually compelling first seconds, you’ll still need to:

• Script the flow
• Cut dead air
• Add titles, device motion, and music

That usually means editing in a separate app or using a tool like Reely that automates those steps.

What’s the best open source screen recorder for Mac performance?

For pure performance and flexibility, OBS is the stronger choice:

• It has more active development (July 2026 release, tens of thousands of commits).
• It supports ScreenCaptureKit-based capture and can handle demanding resolutions and longer sessions.

Kap is lighter and easier, but OBS is the powerhouse if you’re pushing your Mac.

How does Reely compare to Kap and OBS for launch videos?

Kap and OBS are recorders.

Reely is an app launch video generator that integrates with your AI agent and iOS Simulator to:

• Recreate app flows
• Capture them
• Auto‑edit and design the reel with kinetic type, device motion, and audio timing

If you’re an indie iOS dev who wants “promo from code in minutes”, Reely sits on top of your capture tools and replaces most of the manual editing.

For a deeper look at non‑open‑source recorders, cursor zoom tools, and other utilities, check out our pillar guide: Best screen capture software for Mac: complete guide for indie app devs.

And if you’re ready to let your agent build the demo reel too, you can explore Reely at getreely.co.