A free Samsung Members–style diagnostic for any phone
MxMob's full phone diagnostic runs 33 hardware checks straight from Safari, Chrome or Samsung Internet. Tap Test all and it walks through every component in full screen, one after another. Tests that can check themselves run first: the microphone listens for your voice, the speakers are verified by the microphone, the cameras and flashlight are checked frame by frame, vibration is measured by the motion sensor, and touch, sensors, GPS, Wi-Fi, charging, fingerprint or face unlock and the power button pass the moment the hardware responds. Checks that need your eyes, like screen colors and cosmetic condition, come last as a quick yes-or-no question. Every test has Pass, Fail and Skip buttons, and you can retest any single component from the results grid.
How to run the diagnostic
- Open mxmob.com/check on the phone you want to test and turn the media volume up.
- Tap Test all, then Allow access to grant the camera, microphone and location permissions once. They're only used during the test.
- Follow each full-screen prompt. Auto-detected tests run first and move on by themselves. For the few that need your judgement, tap Pass, Fail or Skip.
- Review your score, retest anything that failed, and tap Share report to send the results to a buyer, seller or repair shop.
What each test checks
- Display: full-screen red, green, blue, white, black and gray for dead pixels and OLED burn-in, a grid touch test that must be filled edge to edge, multi-touch, and S Pen or Apple Pencil pressure.
- Audio: left and right speaker tones with a frequency sweep, microphone record and playback with a live level meter, the call earpiece, and wired headphones.
- Camera: live preview of the front camera and every rear lens your phone exposes, with resolution and a photo capture for checking focus, plus the flashlight.
- Sensors: live accelerometer and gyroscope readings, a working compass, the proximity sensor and the ambient light sensor.
- Connectivity: a real Wi-Fi and mobile data speed and latency test, GPS accuracy in feet, a Bluetooth scan, NFC card reading, and a SIM and IMEI check.
- Power: battery level and health, plus automatic detection when you plug in a charger or place the phone on a wireless pad.
- Physical condition: a guided inspection for cracks, dents, battery swelling, lens damage and corroded ports, saved with your results.
- Performance: a 15-second processor benchmark on every core that also catches heat slowdown, plus the graphics chip name, which exposes clones posing as a newer model.
- Buttons & security: vibration motor, volume and power buttons, fingerprint or face unlock, device model, OS version and display refresh rate, and the Widevine DRM level (L1 or L3) on Android, which shows whether streaming apps play in HD and whether the software was modified.
Used phone buying checklist (US)
- Run the full diagnostic and make sure there are no failed tests. Tests for hardware your device doesn't have, such as the earpiece on a tablet, are hidden automatically.
- Dial *#06# and check the IMEI on the free CTIA Stolen Phone Checker so you don't buy a blacklisted phone.
- Confirm the phone is carrier-unlocked if you use a different carrier (Verizon, AT&T, T-Mobile or a prepaid MVNO).
- Samsung Galaxy model numbers ending in U1 are factory-unlocked US models. A plain U means a carrier model.
- Battery health should be 80% or higher, and the seller must sign out of their Apple ID or Google account before you pay.
Frequently asked questions
Is this phone diagnostic test free and private?
Yes. It is 100% free, needs no app or sign-up, and every test runs locally on your phone. Camera, microphone and location data are never uploaded.
Does it work on iPhone and Samsung Galaxy phones?
Yes. Use Safari on iPhone, or Chrome or Samsung Internet on Samsung Galaxy, Google Pixel, Motorola, OnePlus and other Android phones. Tests such as the microphone, speakers, cameras, flashlight, vibration, touch, sensors, GPS, Wi-Fi, fingerprint or face unlock and the power button detect a pass automatically. Where a phone does not expose a component to websites, the test switches to a quick guided check with Pass, Fail and Skip buttons.
How is this different from the Samsung Members diagnostics?
It follows the same one-tap flow: tap Test all, every check opens full screen, many pass on their own when the hardware responds, and you can mark any test Pass, Fail or Skip. Unlike Samsung Members it works on any brand, including iPhone, straight from the browser, and gives you a shareable 33-point report.
What else should I check before buying a used phone in the US?
Run the full diagnostic, then dial *#06# to see the IMEI and look it up on the free CTIA Stolen Phone Checker (stolenphonechecker.org) to be sure it is not reported lost or stolen. Confirm the phone is carrier-unlocked if you plan to switch carriers, check battery health is 80% or higher, and make sure the seller has removed their Apple ID or Google account.
Why did a test fail or not start?
Most failures come from a blocked permission. If the camera, microphone, location or motion sensors never start, tap the lock icon in the address bar, allow the permission for mxmob.com, and retest just that component from the results grid. If a component still does not respond after permissions are allowed, the hardware is likely faulty.