Modern web applications must support any kind of mobile device: from the latest iPhones and iPad to large desktops and laptops. Developers, QA engineers, designers, and marketers suffer from the lack of needed devices or use them inefficiently. Introducing Blisk: a desktop application for mobile testing and cross-device testing on Windows, macOS, and Linux. Blisk combines development and testing processes for mobile and desktop into a single workflow. Blisk users make twice less effort and achieve better results in development and testing compared to regular browsers and other tools. **Top Devices and DevTools.** With top mobiles, tablets, laptops, and desktops that run on iOS, Android, iPadOS, macOS, and Windows, Blisk covers all needs in web development. The list of devices updates constantly. **Features.** - Use devices individually or several at the same time, mix them and share device sets with your team. - The side-by-side view helps to visually compare mobile and desktop and find the code inconsistency easily. - Recreate real-life conditions just like on the device of your end user (slow connection, clean cache, dark mode, landscape orientation, etc). - Find and fix bugs before they become critical. The dedicated error monitoring service works in real-time on each device independently. - Use chrome-like DevTools for each device and a set of advanced developer tools that dramatically improves your performance. **Works everywhere. Uncompromised security.** The source code stays safe because it executes locally and is not transferred anywhere unlike other web solutions. When you browse the web, Blisk provides an extra layer of security by notifying about suspicious files and malicious websites.