Kobo Glo HD Hack: Freeing The E-Reader and Expanding Its Memory

The Kobo Glo HD is a fantastic e-reader, but what truly makes it special is the level of freedom and hackability it offers. This freedom is precisely why I chose it over competitors like the Kindle. In this post I will describe how to disable the intrusive cloud login and perform a major memory upgrade. Despite performed on the GlovoHD, What I write here I probably true for any Kobo device.

Skipping the Cloud and Gaining Independence

One of the best initial hacks is to force the Kobo into local-only account mode, which allows you to completely bypass the online registration and cloud login features. This is a must for those who prefer to sideload all their books and maintain privacy.

To enable local-only mode, you need to edit the Kobo’s configuration file. I did this on a freshly reset device, before you even turn it on the first time.

1. Access the Config File: Connect your Kobo to your PC and navigate to the .kobo/Kobo folder.
2. Locate Kobo Kobo eReader.conf: Open this file using a plain text editor (like Notepad++ or VS Code).

3. Under the [ApplicationPreferences] section, add the following line:

    SideloadedMode=true
   

4. Save and Eject: Save the file, safely eject the Kobo, and reboot.

Now, your Kobo will prompt you for local details instead of forcing a cloud registration, giving you complete sideloading freedom. I have also tested this for the Clara HD version.

The Hardware Fix: Repairing the Micro-USB Port

After few years of usage even a nice device like this can break up. For me the weak spot was the micro-USB connector. It eventually broke, preventing both charging and PC connectivity. So, I had to fix it. I considered upgrading the connector to USB-C but Since I already had similar Surface-Mount Technology (SMT) micro-USB connectors in my home lab, and I rarely need to charge the ebook reader, I decided to stick with the original port type instead of upgrading it.

The Soldering Challenge (Medium Difficulty)

The repair required careful soldering, a task of medium difficulty due to the small size of the contacts:

• Open the Case: the case is not glued but only clicked. so you can open it with help from a flat screwdriver
• Old Connector Removal: I first carefully desoldered the broken port and cleaned the remaining tin residue from the pads on the PCB.
• Alignment and Stabilization: The key was alignment. I placed the new connector, first soldering the two external anchor wings (the large structural tabs). This stabilized the connector perfectly. This worked fine because the new SMT micro usb port was basically identical to the old one!
• Data Pins: Finally, I soldered the four data/power pins to the board. Since the connector was already aligned and stable, this part was straightforward.

The repair was successful on the first attempt! The Kobo was charging and connecting to the PC again.

The Upgrade: 4GB to 32GB Memory Expansion

While the Kobo was open for the USB repair, I couldn’t resist to see what was inside. I immediately noticed an internal MicroSD card. Driven by curiosity, I unplugged the card and connected it to my PC. It turns out, this card is the device’s main storage, housing everything: the OS partition, a Recovery partition, and the Data partition for user books. My Kobo Glo HD came with a small 4GB card…clearly worth an upgrade.

The Expansion Process (From 4GB to 32GB)

The goal was to move everything to a new 32GB card and expand the user storage.

1. Full Image Backup: Using the dd command, I created a byte-for-byte clone of the original 4GB card. This is essential to transfer the OS and partitions exactly as they were.

    # Backup the original 4GB image to a file
    sudo dd if=/dev/mmcblk0 of=~/kobo_reader.img bs=4M status=progress
    # Restore the image onto the new 32GB card (inverse command)
    sudo dd if=~/kobo_reader.img of=/dev/mmcblk0 bs=4M status=progress

1. Resizing the Partition: After the image was restored to the 32GB card, I used disk to modify the partition table. The original image still defined the Data partition (partition 3) size as 4GB, so I extended the Data partition (/dev/mmcblk0p3) to utilize all the newly available space on the 32GB card. This step adjusted the boundary in the partition table.

2. The FAT32 Filesystem expansion: The Data partition was formatted as FAT32. Typically, after resizing the partition, you expand the filesystem to fill the new space. However, When I attempted to use fatresize (e.g., sudo fatresize -s max /dev/mmcblk0p3), the command failed to recognize the filesystem correctly and was unable to complete the resize operation.

The Workaround was basically: Backup, Delete, Recreate. Since direct filesystem resizing failed, I opted for a clean, reliable recreation:

1. I backed up all the original data files from the existing FAT32 filesystem.
2. I re-formatted the data partition as FAT32, ensuring it had the required volume label:

  sudo mkfs.vfat -F 32 -n "KOBOeReader" /dev/mmcblk0p3

1. Finally, I restored the original data files to the new, massive partition.

After inserting the 32GB card and reassembling the Kobo, it booted perfectly! The e-reader now fully recognizes and utilizes the 32GB of expanded memory, a massive increase that is even reflected in the device’s settings menu.

Final Thoughts

With a disabled cloud login, a fully repaired and reliable charging port, and a massive 32GB of internal storage, this Kobo Glo HD is now better than new. This project proves that the Kobo is not just an e-reader but a versatile piece of hardware that truly rewards the technically inclined people with easy to fix hardware and nice freedom… Good job Kobo!

As always I hope you enjoyed this article.