Short answers, then the right deeper page.

AirTag is rated IP67: submersion to 1 meter for 30 minutes. We have rinsed test units under taps, dropped them in dog water bowls, and walked them through downpours; no failures. The IP67 rating does not cover saltwater swims or pressurized water, so we would not strap one to a wetsuit.

About one year on the original CR2032 battery, in our testing. Heavy Precision Finding use shaves a month or two off. Apple says you will get a low-battery alert in iPhone Find My before it dies; that part has worked reliably for us.

Push down on the steel back, twist counter-clockwise, lift the cover, swap the CR2032, twist back. Use Panasonic or Energizer; bitterant-coated cells (most child-safe brands) sometimes lose contact and AirTag will not power on. We have a pictorial walkthrough and a list of which brands work.

Not really. Android can detect a stray AirTag traveling with you (anti-stalking alert) and read its serial via NFC if found, but it cannot ping, locate, or track an AirTag you own. For Android households we recommend Samsung SmartTag 2 or Tile Pro; both offer real Android tracking apps.

Three causes cover almost every case: dead battery (AirTag will refuse to power on with low cells), bitterant coating on a child-safe battery blocking contact, or the AirTag is paired to a different Apple ID and needs reset. Twist off the cover three times in a row to factory reset.

AirTag wins for iPhone households (Precision Finding, 1.5B-device Find My network). Tile wins if you have an Android phone, want a key-ring hole, or need community alerts that work cross-platform. We use AirTags for keys and bags, Tile Pro for laptop bags traveling with non-iPhone family.

Different jobs. AirTag finds a stolen car in dense urban areas where iPhones are everywhere. That can help with theft recovery within a city and is free after the $29 purchase. A 4G GPS tracker streams real-time location anywhere with cell coverage, costs $15-30/month, and is the right answer for fleet management or rural recovery.

Yes, but with trade-offs. AirTag and SmartTag are zero-subscription Bluetooth trackers (one-time $29). True 4G/LTE GPS trackers without subscription exist (Optimus 3.0, Spytec STI) but lock you into a specific carrier or limited check-in frequency. We break down five no-fee tracker types and the catch on each.