Cell Phone Location Tracker +

Cell Phone Location Tracker + is a consent-based location sharing Chrome extension that lets you locate a contact by phone number. You can search by number, request permission, and, after approval, view the person’s location on a map with directions.

Locations update using GPS/GSM/WiFi data when available; if not, it uses cellular data or IP. The extension uses a subscription model via iTunes and provides privacy-conscious controls and clear terms.