iPhone Duo Simulator

DuoBreak, also called iPhone Duo Simulator for Websites, is a browser-based preview tool for developers and designers. Paste a public page URL and the service loads it in a headless browser at the folded 5.4-inch and unfolded 7.6-inch viewports documented on the product site, then returns HD screenshots of both layouts. It flags content that may sit on the center fold, overflow the narrower folded width, or collide with a right-side browser chrome column in the folded preview. Results include a Duo score out of 100 and a list of the issues found. You do not need a Mac, Xcode, or a physical device, and there is no account or subscription. DuoBreak is an independent website; it is not an Apple product, partner, or official simulator. It is not an AI tool.