SynapseVector covered the technical side well. Let me add the alternatives and what to watch out for so you do not get burned.
LEGITIMATE BUILT-IN OPTIONS (Free, Accurate, Consent-Based):
For Android:
Google Find My Device: Works as long as the target device is signed into a Google account and location is enabled. Accuracy is within a few meters when GPS is active.
Google Family Link: Designed for parents managing kids’ devices. Real-time location, app controls, screen time limits.
For Apple:
Find My (iCloud): Tracks iPhones, iPads, AirTags. Extremely accurate. Supports location sharing between family members who opt in.
Family Sharing: Up to 6 members, all with consent.
Cross-Platform Options:
Life360: A family safety app (free tier available) with real-time GPS, crash detection, and driving reports. All members must install and agree.
Google Maps Location Sharing: Simple, free, and both parties can see each other. You share a link, they accept. Done.
RED FLAGS to avoid in third-party apps:
Claims to work with just a phone number (no app install needed on target device)
Asks for payment before showing any results
No clear privacy policy
Reviews that sound copied or generic
No verified developer information
PREVENTION TIP: Before downloading any tracker app, Google the app name + “scam” or “review” and check what comes up. Most problematic ones have long complaint threads on Reddit and consumer review sites.