Demo Studio (demo.bnj.app) is a browser-based tool that turns a screen recording into a polished product demo video. The user either records their screen with the browser's built-in screen capture (getDisplayMedia) or opens a video file they already have (MP4/WebM/MOV). The tool analyses the clip by comparing consecutive frames at low resolution to find where on-screen activity happens, proposes zoom "moves" on a timeline, composites the clip onto a background with a window frame and shadow, and encodes an MP4 frame by frame using WebCodecs. All of this happens inside the user's browser tab. No account, no email, no password. MONETISATION (IMPORTANT — Stripe is LIVE as of 2026-09-03): a paid subscription sold directly on the web through Stripe Checkout. Plans: weekly USD 4.99, monthly USD 14.99, yearly USD 49.99, each starting with a 24-hour free trial that requires a card and renews automatically unless cancelled during the trial. Prices are shown in USD and charged by Stripe. The subscription is unlocked by a licence code of the form BNJ-XXXXXXXX which is shown to the user after payment; there is no account, so the licence code is the only way to restore a subscription on another device. Free users get a 30-second, 1080p, 30fps export with a small corner watermark; the paid plan removes the watermark and the length limit and unlocks 1440p/2160p, 60fps, custom backgrounds and saved styles. CANCELLATION AND REFUNDS: the subscription can be cancelled at any time from the Stripe customer portal, reachable from the app itself; cancellation takes effect at the end of the paid period and the plan keeps working until then. Cancelling during the 24-hour trial costs nothing. Refund policy: no charge is made during the trial; after a renewal, a refund is given if the request arrives within 14 days and the plan has not been used in that period; statutory consumer rights are unaffected. Prices may change, but only with notice before a renewal.