Free-to-try stud finder app for iPhone & Android.

Yes. Stud Finder is free to download with a free trial on the App Store and Google Play, and it is completely ad-free. After the trial, a subscription unlocks unlimited scanning. Many apps listed as "free" instead hide a paywall behind a fake scan or bury detection under ads — check the "Offers In-App Purchases" line and recent reviews before you trust the claim.

Yes — the ones that genuinely read the magnetometer. The thirty-second test: open the app, hold the phone near a doorknob or any metal object, and watch the reading. If it spikes, the app is reading the real sensor and will find fasteners in a wall; if nothing moves, the scan is fake regardless of what the listing promises.

Because the magnetometer is already in your phone, so detection costs nothing to run — that's why almost every stud finder is free to download. A subscription funds ongoing development and keeps the app ad-free; we'd rather charge for the app than fill it with ads or sell your data, which is how most "free" stud finders actually make money.

No ads at all — no banners, no interstitials, nothing during the scan. Detection is full-featured during the free trial; after the trial, a subscription keeps unlimited scanning unlocked.

The honest limitations: it works best on standard drywall-over-wood walls (not metal studs, masonry, or thick plaster), Android detection quality depends on your phone's sensor, and it's one measurement — for heavy mounts, confirm with a hardware finder. On cost, it's free to try, then a subscription, with no ads either way.

A stud finder app that actually reads the magnetometer works just as well as any other — the underlying sensor is the same. What separates good from bad apps is whether the app really uses the magnetometer (not a fake animation), whether it runs offline, and whether it is ad-free and honest about pricing.