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Musaed Alenezi
Musaed Alenezi

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I built a free browser tool to test any phone before buying it (no install needed)

Buying a used phone is risky.

You never really know if:

  • The touch screen has dead zones
  • Sensors (gyro, proximity) actually work
  • The battery is degraded
  • The device has hidden performance issues

Most people just check the basics and hope for the best.


So I built a solution for myself

I created a browser-based tool that runs a full diagnostic test on your phone — no app install needed.

It tests things like:

  • Touch screen accuracy (with grid detection)
  • Display quality
  • Audio & microphone
  • Motion sensors
  • Camera
  • CPU & performance
  • Network & storage
  • Vibration & more

Why browser-based?

I wanted something:

  • ✅ Fast (no downloads)
  • ✅ Private (runs locally)
  • ✅ Works on any device (Android / iOS)

Real use case

This is especially useful if you're:

  • Buying a used phone
  • Selling your device and want proof it works
  • Troubleshooting hardware issues

Try it here

https://appfixing.com/device-doctor/


I'd love your feedback

  • What tests would you add?
  • Any ideas to improve accuracy?
  • Would you trust browser-based diagnostics?

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