Getting started

Lagsmith needs macOS 13 Ventura or later, on Apple silicon or Intel.

1. Download and install. Download Lagsmith, move it to Applications and open it. Its icon appears in the menu bar.
2. Allow the network extension. macOS asks you to allow Lagsmith’s network extension. Open System Settings when prompted and allow it. You only do this once.
3. Pick an app. Click the menu bar icon and pick a running Mac app or an app in a booted iOS Simulator.
4. Choose conditions. Choose a preset such as 3G, or a failure mode such as Airplane Mode. Only that app is affected.

About the network extension

To control one app’s network without touching the rest of the Mac, Lagsmith installs a network extension. This is the standard way macOS lets apps work with network traffic, and macOS always asks you to approve it. Lagsmith can’t throttle anything until it is allowed.

If you missed the prompt, see troubleshooting.

Your trial

Every install starts with a 14-day Pro trial with everything unlocked. After that, the free version keeps working. Pricing.

Next

• Presets and custom conditions
• Failure modes
• Request monitoring