MxMob Docs: free online phone test & phone diagnostic guide

Every phone also has its own built-in diagnostics. Our brand guides show how to open them, read the results and check battery health:

• Samsung Galaxy diagnostics
• iPhone diagnostics
• Google Pixel diagnostics
• MacBook diagnostics
• Dell diagnostics
• HP diagnostics
• Lenovo diagnostics
• Microsoft Surface diagnostics
• Chromebook diagnostics
• ASUS diagnostics
• Acer diagnostics
• Windows laptop diagnostics

Short version: iPhone diagnostic test options are limited to Settings (Battery Health, Parts and Service History) and Apple Support’s remote diagnostic, so the browser test fills the gap. Samsung diagnostic test: dial *#0*# or use Samsung Members (many US carrier models block the code). Pixel diagnostic: *#*#7287#*#* opens the Pixel Diagnostic app.

Laptop & PC diagnostics

The laptop diagnostic test checks Windows laptops, MacBooks and Chromebooks in one run: keyboard, trackpad and mouse, webcam, speakers, display, Wi-Fi and USB ports. Single tools cover the click speed test, backlight bleed, monitor refresh rate, screen resolution and game controllers. For battery wear, use the operating system’s report; the laptop battery health guide shows where on Windows, macOS and ChromeOS. For SSD health, memory tests and the built-in Dell, HP, Lenovo and Apple diagnostics, see how to test laptop hardware. For webcam and microphone problems before a Zoom, Teams or Google Meet call, see the webcam and mic test guide.

Live Remote Inspection: inspect a used phone or laptop from anywhere

Live Remote Inspection is for buying a used device you can’t hold: a Facebook Marketplace, eBay, Swappa, OfferUp, Mercari or Craigslist seller in another city or state. The seller opens one link on the device and runs the MxMob tests; you watch every result appear on your own screen, live, and send checks they can’t prepare for. It’s self-serve software: nobody from MxMob joins the session, and neither of you installs an app. The step-by-step guide with screenshots walks through a real session.

For buyers

1. On mxmob.com/inspect, choose Phone / tablet or Laptop / PC and enter what the listing claims (model, storage, color, listing link). Then press Start free inspection; no payment or card is needed.
2. Your private buyer console opens with a seller link and QR code. Send it by text, WhatsApp, email or marketplace chat. Keep the console address: it is your key to the inspection.
3. When the seller connects, you see the live view (camera preview during camera tests, touch map, microphone level), each test result labelled Measured or Marked by seller, and a panel comparing the detected model, software, screen and graphics chip with the listing.
4. Send live checks at any time and chat with the seller. Ask them to run any test that hasn’t been done.
5. End the inspection to create the signed record. Sessions close by themselves 3 hours after the seller joins.

For sellers

Open the link on the phone or laptop you are selling (the page warns you if you open it on the wrong kind of device), read what will be shared, tick the box and tap Start live inspection. The buyer sees test results, the device model and browser, a low-resolution camera preview only during camera tests and photo checks, photos you take for them, the microphone level (never audio), and anything you type for them, such as the IMEI. Nothing else on the device is accessed, and you can stop at any time by closing the page.

Live anti-scam checks

• Mirror code: a random code is shown full screen; the seller photographs the device in a mirror with its front camera, proving that exact device is running the test.
• Speaker code: the device reads out a 4-digit code the seller types back.
• Tap the squares: you pick 4 to 8 squares; the seller taps them on their screen.
• Back in a mirror (phones): the rear camera photographs the device’s own back and its scratches, for comparison on delivery.
• Ask for a photo: charging port, screen corners, the Battery Health or About screen, anything you name.
• IMEI (phones): typed from *#06# with a check-digit test. No website or app can read it automatically, so the record says it was typed by the seller.

The signed record and the handover check

The record holds every result, live check, photo, the device details, the chat and a timeline. It is signed by MxMob so it can’t be edited, kept for 90 days at a private link, and anyone with the record code can verify it on the inspection page. When the device arrives, open the handover check from your record on the device you received: it compares the IMEI, model, screen and graphics chip with the inspection, shows the photos so you can match the marks, and re-tests the parts. See the sample record.

Limits

If the seller never opens the link within 6 days, it expires; start a new inspection at any time, for free. Browsers can’t read exact storage size, battery cycle count, water damage or activation locks, so ask for photos of those screens and confirm the activation lock on delivery.

Report links for sellers and buyers

After a diagnostic, sellers can create a report link (mxmob.com/r/…) with a QR code, a badge image and ready-to-paste listing text for eBay, Facebook Marketplace, Swappa and others. It shows each result labelled measured or marked by the seller and the last 4 digits of the IMEI to match in person, and expires after 30 days. See sell your phone with a test report; buyers can check a seller’s report. A report link is run before the buyer asks; a live inspection is run while they watch.

Checking a used phone or laptop before you buy

Hardware tests only tell part of the story. A phone can pass every test and still be locked to someone else’s account or reported stolen. Work through the used phone checklist (also in Hindi and Urdu) or the used laptop checklist, and read:

• How to test a used phone before buying online
• How to check a used iPhone: Activation Lock, IMEI and replaced parts
• How to check if a phone is stolen with the IMEI
• How to check if a phone is original or fake
• Buying a used phone in India

Charging tools

The charger checker, USB-C cable checker, power bank calculator and wireless charging test compare published specifications: the standards your phone supports (USB Power Delivery, PPS, Qi2, MagSafe) against what the charger and cable deliver. Real-world speed also depends on temperature and battery level, so treat the numbers as the best case. If your phone charges slowly, read the slow charging checklist.

Reading the results sensibly

• A fail is a lead, not a verdict. Run that single test again, restart the phone, and try the manufacturer’s own tool (see the brand guides) before paying for a repair.
• Speed tests reflect the network, not just the phone. A slow Wi-Fi speed test in a crowded café says more about the café. Compare with another phone on the same network.
• Battery health isn’t available to websites. Use the phone’s settings; the battery health guide shows where on each brand.
• Refresh rate can read lower than the screen supports. Low Power Mode and some browsers cap pages at 60 Hz, even on a 120 Hz display.
• The water eject tone may help, but isn’t a repair. It can shake droplets out of a speaker grille; it won’t fix a damaged speaker or dry the inside of the phone. See muffled speaker fixes.
• Dots on the screen? Our guide to dead vs stuck pixels explains which can be fixed with the stuck pixel fixer.

Troubleshooting

• Camera or microphone blocked: in Safari, tap aA in the address bar › Website Settings and set Camera and Microphone to Allow. In Chrome, tap the icon left of the address › Permissions. Then reload the test.
• Motion sensors show nothing on iPhone: Safari only asks once. Close the tab, open the sensor test again and tap Allow.
• No sound on iPhone: check the silent switch or Action button; silent mode mutes web audio. Then retry the speaker test.
• Touch squares won’t fill at the edges: remove a thick case or a lifted screen protector and retry the touch test. If the same strip fails, the digitizer is damaged.
• Screen taps by itself: run the ghost touch test and follow the ghost touch guide.
• Laptop keys don’t register: see laptop keyboard keys not working.

Your data & privacy

• Camera, microphone, motion sensor, location and biometric checks happen in your browser. Nothing from them is uploaded, and access stops when you close the tab.
• The speed test sends and receives blank test data from our server. We don’t store the result.
• We count which pages are opened and which tests pass or fail, without an IP address, cookie or identifier. This is how we notice when a test is broken on a particular phone. Do Not Track and Global Privacy Control turn it off.
• If you send feedback at the end of a diagnostic, we store what you send so we can fix problems.
• If you create a report link, we store that run’s results and the device details you added (with the IMEI cut to its last 4 digits) for 30 days. Anyone with the link can open it; you can delete it sooner.
• A Live Remote Inspection record, its photos and handover checks are kept for 90 days, then deleted.

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