App Demo Video Tools With a CLI or MCP Server: Capture Once, Then Scale With Screen Studio and Reely

Overview: Why Combine Screen Studio and Reely for App Demo Videos

If you ship iOS features faster than you can market them, you need a demo workflow that feels like code, not ceremony.

This tutorial walks through a practical, end-to-end workflow using two complementary tools:

• Screen Studio for high-quality initial capture and quick manual polish
• Reely for AI-native variant generation via CLI/MCP server integrated with your coding agent

You’ll learn how to:

• Capture once in Screen Studio
• Create a clean master sequence
• Hand off that sequence and your app build to Reely
• Use Reely’s macOS app and MCP tool to generate multiple demo variants from code and specs

This article supports the deeper pillar guide “Keeping Marketing Assets in Sync With Your App Code” on the Reely blog, where we zoom out and cover broader strategies for keeping launches aligned with your repo.

Prerequisites

Before you follow the steps, make sure you have:

• macOS running Ventura 13.1+ (Screen Studio’s recommended baseline)
• Xcode + iOS Simulator installed
• Screen Studio (paid plan recommended; unpaid plans gate exports)
• Reely for macOS (AI-native app launch video generator)
• An iOS app build ready to run in Simulator
• (Optional but recommended) An AI coding agent that supports MCP tools (e.g. Claude, ChatGPT, Cursor, VS Code)

You should be comfortable with:

• Running your app in Simulator
• Basic CLI usage
• Prompting an AI agent with feature specs

Step 1: Plan Your Core Demo Flow Once

Before hitting record, lock in a single source-of-truth flow. This improves both your Screen Studio edit and Reely’s reconstructions.

1.1 Define the feature beats

Write a concise, structured outline:

• Entry point: where the user starts (e.g. home screen, onboarding)
• Key interactions: taps, scrolls, modal opens
• Outcome: what success state looks like (e.g. saved note, completed order)
• Message: 1–2 sentences you want viewers to walk away with

Example for a habit-tracking app:

• Open app → Today view
• Add new habit → pick icon and cadence
• Mark habit as complete → confetti state
• Close with tracking streak summary

1.2 Align the flow with launch channels

Decide which formats you’ll need:

• App Store preview (landscape, 30–35s, clear UX)
• Product Hunt trailer (30–60s, story-driven)
• X/LinkedIn/YouTube Shorts (10–20s feature teaser)

You’ll capture once, then use Reely to adapt this core flow to each channel.

Step 2: Capture a High-Quality Master in Screen Studio

Screen Studio is currently one of the strongest "capture once, polish fast" tools on macOS.

Its public docs highlight:

• Automatic zoom
• Smooth cursor movement
• Manual zooms and pans
• Vertical exports and device recording
• Presets, captions, trimming, and speed changes

2.1 Record the app flow in iOS Simulator

1. Launch Xcode and your app in iOS Simulator.
2. Open Screen Studio and start a new recording.
3. Select the Simulator window or full screen, depending on your framing.
4. Run through your planned flow slowly and deliberately:
   • Pause briefly before each key tap
   • Avoid interruptions or notifications
   • Complete a clean, uninterrupted run

Tips:

• Do 2–3 takes; choose the best one.
• Use Screen Studio’s automatic zoom to emphasize crucial gestures.

2.2 Clean the master sequence in Screen Studio

After recording:

1. Trim the start and end to remove setup and tail dead time.
2. Use speed-up edits for slow transitions (loading states, scrolling).
3. Add captions or overlays for clarity (e.g. "Create a new habit").
4. Export a high-quality master file:
   • 4K or high-res HD
   • Neutral aspect ratio (e.g. 16:9) for flexibility

This Screen Studio master becomes your reference capture and a fallback asset for static contexts (e.g. website embeds).

You now have:

• One polished, human-reviewed recording
• A clear timeline of user actions

This is where you stop timeline-heavy editing and move into AI-native, agent-first workflows.

Step 3: Decide When to Hand Off From Screen Studio to Reely

The handoff point is critical. Use Screen Studio for capture + first polish, then switch to Reely when you need speed and variants.

Hand off to Reely when:

• You need multiple versions of the same demo (App Store, Product Hunt, social)
• Your app UI changes frequently and re-recording every time would be painful
• You want your coding agent to participate in the motion workflow

Stay in Screen Studio when:

• You’re producing one-off explainer videos with heavy narration
• You need very manual, bespoke motion outside app footage (e.g. complex tutorials)

In practice, most indie iOS devs and small teams benefit from:

• Screen Studio as the "capture once" foundation
• Reely as the "render many" system for launch campaigns

Step 4: Set Up Reely’s macOS App and MCP Tool

Reely is an AI-native app launch video generator built specifically for mobile developers.

Key capabilities relevant to this workflow:

• macOS app that renders locally (no cloud upload)
• Deep integration with iOS Simulator
• MCP/agent tool so your coding agent can go from "build feature" → "build demo reel" in the same workflow
• Outputs:
  • 10–20s feature teasers
  • 30–60s full launch promos

4.1 Install and connect Reely

1. Download and install Reely for macOS.
2. Grant access to Xcode’s iOS Simulator.
3. Configure Reely to:
   • Use your existing app build
   • Access local render settings (4K, preferred aspect ratios)

4.2 Enable the MCP server for your agent

Reely exposes an MCP tool so AI agents can:

• Discover the tool automatically based on context
• Call Reely to recreate flows in Simulator
• Record, trim dead air, and send footage into Reely’s motion engine

In your MCP-enabled client (Claude, ChatGPT, Cursor, VS Code plugin):

1. Add Reely’s MCP server configuration.
2. Restart the client or reload tools so your agent can see Reely.
3. Confirm by asking your agent:

"List available MCP tools for app demo video generation."

You should see Reely in the returned tool list.

Step 5: Use Your Agent + Reely to Reconstruct the Demo Flow

Now you can move from manual capture to agent-driven reconstruction.

Reely’s agent can:

• Launch your app in iOS Simulator
• Follow your scripted flow
• Record clean footage
• Automatically remove dead air

5.1 Feed the agent your Screen Studio flow

Take the outline you used in Screen Studio and turn it into a prompt:

Example prompt:

"Using the Reely MCP tool, run the iOS app in Simulator and record a demo that:

1. opens the Today view, 2) creates a new habit with a weekly cadence,
2. marks the habit complete to show the confetti state, and 4) ends on the streak summary. Keep the recording under 25 seconds and remove dead air."

The agent now has:

• Your original flow
• Access to Reely’s MCP tool
• Control over the Simulator

5.2 Capture programmatically via MCP

Your agent will issue MCP calls such as:

• reely.launch_simulator(app_id)
• reely.record_flow(steps=[...])
• reely.trim_dead_air(target_duration=25)

The result:

• A fresh, in-sync recording that reflects the latest code
• Footage already optimized for Reely’s motion studio

This replaces "open Screen Studio, manually re-record" with "describe the flow, let the agent and Reely rebuild it."

Step 6: Turn Footage Into Multiple Reels With Reely

With footage in Reely, you can generate multiple launch-ready outputs from the same source.

Reely’s motion system includes:

• Thirteen typography systems
• Device choreography presets
• Music and sound cue timing
• Editorial pacing tuned specifically for product demos

6.1 Generate a 10–20s feature teaser

In Reely’s macOS app (or via MCP), configure a short teaser:

• Target length: 15–20 seconds
• Aspect ratio: 9:16 for X/LinkedIn/Shorts
• Focus: one core interaction (e.g. "Create and complete a habit")

Prompt example:

"Create a 15-second vertical feature teaser highlighting how fast it is to create and complete a new habit. Use kinetic typography for the phrase 'Ship habits, not excuses' and keep pacing tight with minimal dead air."

Reely will:

• Apply device choreography (subtle pans, zooms)
• Add kinetic text aligned with beats
• Sync music and sound cues to transitions

6.2 Generate a 30–60s full launch promo

For more narrative channels (Product Hunt, launch threads):

• Target length: 35–45 seconds
• Aspect ratio: 16:9 or 1:1 depending on platform
• Structure: problem → feature demonstration → outcome

Prompt example:

"Create a 40-second launch promo for our iOS habit tracker. Start with a title card stating 'Busy devs, simple habits.' Show the full flow of creating a habit, completing it, and viewing streaks. Add section headers for 'Plan,' 'Tap,' and 'Win' as kinetic typography. Prioritize clarity over speed."

Reely outputs:

• One long-form promo and one short teaser
• Multiple aspect ratios
• 4K masters

All from the same underlying app flow and source code.

Step 7: Keep Assets in Sync With Code Over Time

The biggest win of agent-first tools like Reely is keeping marketing assets aligned with your actual app.

According to Wyzowl’s 2026 survey:

• 91% of businesses already use video as a marketing tool
• 93% of video marketers say video is important to their strategy
• 19% mostly create screen-recorded video — exactly the format app demos live in

As your app evolves:

• Your Screen Studio master remains a reference for tone and pacing
• Reely’s MCP-driven flows recreate current UI on demand

Whenever you ship a feature or UI change:

1. Update the flow spec (your step-by-step outline)
2. Ask your agent to rerun the Reely MCP workflow
3. Regenerate:
   • New feature teaser
   • Updated launch promo
   • Any platform-specific variants

Instead of "record everything again" you have "describe what changed and re-render."

For a broader strategy, see the related pillar article “Keeping Marketing Assets in Sync With Your App Code” on the Reely blog, which covers CI-based triggers, branching strategies, and governance.

Step 8: Optional — Tie Reely Into CI for Auto-Generated Reels

If you’re comfortable with CI/CD, you can push this workflow further.

Conceptually, you can:

• Use a CI tool to trigger Reely after successful builds
• Automatically generate fresh demo reels from build artifacts
• Store outputs alongside your release notes

A high-level CI flow:

1. On main or release/* build success:
   • Run automated UI tests
   • Confirm key flows still pass
2. Trigger a demo generation job:
   • Call your MCP-enabled agent with a "Generate demo reels" instruction
   • Agent uses Reely’s MCP server to record key flows
   • Reely renders updated teasers and promos
3. Publish outputs to:
   • Internal launch docs
   • Asset library for marketing

This "app demo reel auto-generate after build" pattern keeps your motion assets as fresh as your code.

When to Use Screen Studio vs Reely: Quick Reference

Use this as a mental model for the combined stack.

Start in Screen Studio when:

• You’re crafting the first-ever demo for a new product
• You want hands-on control over cursor movement and manual zooms
• You need a single, polished explainer-style video

Hand off to Reely when:

• You need multiple variants from the same flow
• Your app changes weekly and you don’t want to re-record manually
• You want your AI coding agent to own the demo workflow via MCP
• You care about local rendering and privacy (no cloud uploads)

Together, you get "capture once" from Screen Studio and "generate many" from Reely.

FAQ: CLI, MCP, and App Demo Video Tools

What is MCP and why does it matter for app demo videos?

The Model Context Protocol (MCP) is an open protocol for connecting AI models to external tools and data sources.

Official docs say MCP now works across major clients like Claude, ChatGPT, VS Code, and Cursor, and Anthropic reports MCP SDK downloads exceeding 400M monthly, up 4x this year.

For app demos, MCP means your agent can:

• Discover tools like Reely automatically
• Invoke them programmatically
• Follow full workflows from "build feature" to "build demo reel" without manual intervention

How does Reely differ from generic AI video generators?

Reely is explicitly built for app launch videos and mobile developers, not generic stock footage.

Key differences:

• Deep iOS Simulator integration
• Local rendering on macOS (no cloud uploads)
• Studio-level motion system for device frames, kinetic type, pacing, and sound
• Agent-first design via MCP, so your coding agent can create demos from code and app flows

Generic AI video tools usually don’t:

• Understand real app flows
• Tie directly into your build artifacts or Simulator
• Respect local-first, privacy-preserving workflows

Can I use Reely without Screen Studio at all?

Yes.

You can rely entirely on:

• Reely’s agent-driven capture in Simulator
• Its motion systems for promos and teasers

However, many teams find Screen Studio useful for:

• The very first hand-crafted master
• Complex manual tutorials where human timing matters

After that, Reely takes over for speed and scale.

How does this workflow help with social-first video distribution?

Wistia’s 2026 data shows LinkedIn is now the primary video channel for 8 in 10 teams, and social engagement is the top metric for almost a quarter of marketers.

Short-form demo content is ideal here.

Using Screen Studio + Reely:

• Screen Studio gives one polished reference recording
• Reely produces multiple short, social-ready variants (9:16, 1:1, platform-specific pacing)
• MCP lets your agent spin up fresh variants quickly as features evolve

Do I have to upload my builds to the cloud for this workflow?

No.

Both Screen Studio and Reely are macOS-local tools:

• Screen Studio records locally and gates exports based on your license
• Reely’s macOS app renders locally, uses Xcode’s iOS Simulator, and does not require cloud uploads for your builds

This is ideal if you care about privacy, self-hosted workflows, or sensitive app data.

By combining Screen Studio’s capture strengths with Reely’s AI-native, MCP-driven motion pipeline, you get a workflow that respects your time as a builder:

• Capture once
• Describe flows instead of re-recording
• Let your agent and Reely keep marketing assets in sync with your app code.