Compare software

PolypaneLT Browser
Paid

A paid subscription is required after the trial.

 Freemium

Free to download, with paid tiers as part of the TestMu AI platform.

Windows, macOS, Linux, Browser extension Windows, macOS, Linux
  • Accessibility simulation and checks built into the browser itself
  • Synchronised panes with live CSS editing across all of them
  • Views several device viewports side by side
  • More than 50 device screen presets
  • Paid subscription with no free tier beyond a trial
  • Chromium rendering only
  • Device views are emulated rather than real hardware
  • Tied to a commercial testing platform with paid tiers
Downloadable app, Browser extension Downloadable app
Closed source Closed source
License not stated License not stated
Not stated if an account is needed Not stated if an account is needed
Not stated if it works offline Not stated if it works offline

Checked September 22, 2026

Checked September 23, 2026

Catalog facts only. Anything “not stated” is unconfirmed. Check full listings for details.