iOS Stop App

iOS Stop App

Overview

Stops the iOS app running on a connected iPhone by sending SIGTERM signal to the app process. This cleanly terminates the app, allowing it to perform cleanup operations before exiting.

When to Use

Invoke this skill when the user:

• Asks to "stop the app"
• Wants to "kill the app"
• Says "terminate the app on device"
• Mentions shutting down or closing the app
• Needs to stop before deploying new version

Prerequisites

• iPhone connected via USB
• pymobiledevice3 installed (pip3 install pymobiledevice3)
• Device trusted
• App must be running on the device

Instructions

1. Navigate to the iOS app directory:

   cd path/​to/​ios/​app
   

2. Run the stop script:

   ./​stop-app.sh
   

3. The script will:

   • Auto-detect the connected iPhone
   • Find the app's process ID using pymobiledevice3
   • Send SIGTERM signal to terminate cleanly
   • Report success or if app wasn't running

4. Inform the user:

   • The app has been stopped
   • Safe to call even if app isn't running
   • Use SIGTERM (not SIGKILL) for clean shutdown

Expected Output

When app is running:

🛑 Stopping NoobTest on device...
✅ App stopped

When app is not running:

🛑 Stopping NoobTest on device...
⚠️  NoobTest is not running

How It Works

The script:

1. Uses xcodebuild -showdestinations to get device ID
2. Runs pymobiledevice3 processes pgrep NoobTest to find process ID
3. Extracts PID from output
4. Uses xcrun devicectl device process signal to send SIGTERM

SIGTERM vs SIGKILL

The script uses SIGTERM (signal 15), not SIGKILL:

• SIGTERM allows the app to clean up (save state, close connections)
• SIGKILL would force immediate termination without cleanup
• SIGTERM is the proper way to stop an app during development

Common Use Cases

Before deploying new version:

./​stop-app.sh
./​install-device.sh

Pairing with restart:

./​stop-app.sh
# Make changes
./​restart-app.sh

Clean state testing: Stop the app, clear data/​caches manually, then restart fresh.

Common Issues

pymobiledevice3 not found:

• Install it: pip3 install pymobiledevice3
• Ensure Python bin directory is in PATH

No device detected:

• Check USB connection
• Ensure device is trusted
• Try disconnecting and reconnecting

App not stopping:

• Check app is actually running on device
• Try restarting the device if process is stuck

Safety

This script is safe to call repeatedly:

• Won't error if app isn't running
• Uses clean shutdown signal
• Reports status clearly

Bundle ID

The script is configured for the specific app's bundle ID (e.g., com.miso.noobtest for Firefly/​NoobTest). Different apps have different bundle IDs.