Google Calendar Hours Calculator runs only on calendar.google.com. There it downloads the account's own calendar export (Settings, Import & export) with the existing session and reads title, start/end time and your own reply of each event, plus the colour of the events on screen. Hours are added up in the browser; the calendar data is kept in memory only, never stored or sent anywhere. Settings stay in local browser storage. The only data sent out is the email address you enter to buy or restore Pro: it goes to Stripe (payment) and to the developer's license API (https://lakeside-ext-api.expo.app), which only answers whether a purchase exists. No analytics, no tracking. Full policy: https://lakesideapps.expo.app/extensions/privacy/ · Contact: scanlystudio.support@proton.me