I've been asked if I can check some faulty behavior of a device, a cheap Chinese android smartphone.

I'm not really an android expert, usually I install a few apps to help me figure out few things about the device. These apps I've reported conflicting results compared to what was displayed in the main android settings area:

- With [DiskUsage][1] internal memory is reported as 3.9gb vs 16gb in system settings.
- [Device Info HW][2] (suggested by @alecxs) explicitly mark as fake the reported version 9.0, pointing Android 6 as correct with API level 23. Unfortunately the app reports the same storage size of 16gb as stated in system settings. In my previous attempt I've [CPU Info][3].

This kinda reminds me of fake USB thumb drives scams with less memory than advertised.

So is there a way (preferably without root) to test/analyze common technical details of a device for possible tampering/spoofing? 

Like
- Storage
- Android version
- RAM
- CPU
- Something else that can be faked?

FLOSS solutions are highly appreciated! :)

**UPDATE**

Listed used apps and updated after suggestions in comments.


  [1]: https://f-droid.org/en/packages/com.google.android.diskusage/
  [2]: https://play.google.com/store/apps/details?id=ru.andr7e.deviceinfohw
  [3]: https://f-droid.org/en/packages/com.kgurgul.cpuinfo/