Continuous Emergency Web Tracking

I have a working browser-based application that lets a user share their real-time location in an emergency. Everything functions perfectly while the tab is in the foreground, but the moment the browser is minimised or the phone screen locks, the geolocation updates stop... (Budget: ₹600 - ₹1500 INR, Jobs: Android, Backend Development, Frontend Development, Geolocation, JavaScript, Mobile App Development, PhoneGap, Web Development)