Tips for Kindle Fire HD 8 dot 9

Tips for Kindle Fire HD 8.9"

I'm owner of this device since June 2013. And I'd like to share some tips with you.

Thinking about buying Kindle Fire Tablet?

I bout Kindle Fire HD 8.9" for very simple reason - it was most cheap Tablet with full HD display resolution (1080p). Such resolution comes very handy when reading PDF files (they can't be reformatted so high resolution is absolute must).

However I later found several unexpected limitations:

• No Chrome browser available (Kindle has Amazons's browser called Silk)
• No Google Play store access - you can easily access Amazon App Store only which contains only little fraction of Android applications
• Missing many national keyboards (Czech in my case)

NOTE: some of above problem can be workarounded (for example you can install some Google Play apps to your mobile phone with Android OS and transfer it to Kindle - but it is unexpected mess.

Easy non-root shell in Kindle

To start exploring your Kindle device - I recommend QPython - Python on Android available from: https://www.amazon.com/gp/product/B00AP36S4Y/ (I have installed version 1.3.3)

• Launch this QPython app
• Once Python logo appears (on black background) - swipe it to left
• Than click on Console
• You should get Python Console.

How to turn Python Console to shell Console:

1. If your console text start with something like:

   ..../qpython.sh && exit

   Then you can use this simple command to get shell:

   exit(1)

   NOTE: exit( non_zero ) is required to skip evil && exit command which would otherwise close our console

2. If above thing does not work, you can try to invoke shell directly from python langugage using:

   import os
   os.system('sh')

Once any of these command work, you can try for example:

• getting ARM CPU info:

  cat /proc/cpuinfo
      Processor       : ARMv7 Processor rev 10 (v7l)
      processor       : 0
      BogoMIPS        : 2982.32
      ... (it seems that there are 2 cores?)
  

• Getting memory info:

  cat /proc/meminfo
      MemTotal:         786084 kB
      ...
  

  Ooops, you can see that this kindle has just 780MB of RAM installed

• Using package manager to list installed packages in format `PATHANE=PACKAGE_NAME:

  pm list packages -f
      package:/system/app/AmazonJacksonApk-release.apk=amazon.jackson19
      package:/system/framework/framework-res.apk=android
      package:/system/app/air_runtime_dcts.apk=com.adobe.air
      package:/data/app/com.amazon.ags.app-1.apk=com.amazon.ags.app
      ...
  

  Interesting notes:

  • packages located in /data/app directory - are so called User packages - they can be stopped, disabled or removed by user
  • packages located in /system/app are system packages - they can't be disabled nor uninstalled. If you attempt to kill them they start again (ehm)...

• Also these common unix commands works:

  cat   # catalog (show file)
  df    # free space on volumes
  dmesg # show kernel messages
  id    # show your uids and groups (=unix rights)
  mount # show mounted volumes
  ps    # show process list
  set   # show envirnment variables
  top   # show process list each X seconds
  

• Please note that these commands are missing:

  cp   # not avilable - use "cat source_file > destination_file" to replace missing "cp" command
  grep # not available
  sed  # not available
  

• Crude way to backup apps:

  • use above pm list packages -f to find Path of App to backup, for example PDF Max from https://www.amazon.com/gp/product/B00RDSHI66/:

    pm list packages -f
        ...
        package:/data/app/com.mobeera.pdfmax-1.apk=com.mobeera.pdfmax
        ...
    # "backup" command
    cat /data/app/com.mobeera.pdfmax-1.apk > /mnt/sdcard/Download/data/app/com.mobeera.pdfmax-1.apk
    

    NOTE: once you have ADB connection working there exists many other ways how to backup files (either adb pull file or adb backup st...) - but that is another story

  • You can than connect your device via USB cable and normally access Download folder from your Windows/Linux OS

    NOTE: Sometimes that files does not appear in OS List - in worst case restart of Kindle should reload everything and show that file.

Additional Tips for QPython Console:

• Please click on Special Keys to see common Hot-key mapping, for example:
  • Volume Up+w = Arrow Up (got previous command in shell history)
  • Volume Up+t = Tab (expand path in shell)
• Use exit command to Exit current shell and close Console window

Enabling Android Debugger (ADB)

TODO

--hp