Attach TrackR to keys, wallets and more. When an item goes missing, just tap the TrackR app to make your Bluetooth tracker ring loudly.
If you're looking for GPS capabilities, the initial costs can be high but you'll also be paying a (monthly) recurring fee for GSM/cellular data. The return on spend may be justified on a larger bird but probably not the Tello, IMO. Your $$ to spend. Caveat emptor.
Buy Tracki 2020 Model Mini Real time GPS Tracker. Full USA & Worldwide Coverage. For Vehicles, Car, Kids. Magnetic Hidden small Portable Tracking Device. Child, elderly, Dog pet drone motorcycle bike auto: GPS Trackers - Amazon.com ✓ FREE DELIVERY possible on eligible purchases
Buy Marco Polo Ultralight Drone/UAV/Model Rocket Location and Recovery System - No GPS or Cell Service Required - No Monthly Fees - Never Lose your Drone Again - Starter System for 1 Aircraft: GPS Trackers - Amazon.com ✓ FREE DELIVERY possible on eligible purchases