Why can't the Kindle UI be customized?

[BionicGecko]

Sorry if this was asked before, I did try to search the forum but nothing relevant came up.

Jailbreaking is great and makes a lot of cool things possible on our kindles, however one thing that seems out of reach is the customization of the official kindle UI. For instance, I would love to be able to configure the "pinch" gesture to change the brightness instead of the font size.

Now I only own kindles, so my understanding of other platforms is limited, however from browsing the Kobo forums it seems that the UI of Kobos can be patched to add new features or change existing functionality.

Why is this not possible on Kindles? Considering the source code is available for download on the Amazon website, what prevents us from compiling custom versions of the firmware with new functionality included? Wouldn't a jailbroken kindle be able to run such "unsigned" firmware?

Thanks!

[JSWolf]

Because Amazon prefers to keep the Kindle locked-up tight.

[BionicGecko]

Originally Posted by JSWolf

Because Amazon prefers to keep the Kindle locked-up tight.

Thanks Jon, Amazon indeed does.

I guess I was more looking for a technical reason, seeing that we both have a working jailbreak and the source code. I’m not a very skilled developer myself so clearly I’m missing something

Is it perhaps that the available open source code only cover part of the kindle OS, so a fully functional .bin image cannot be built from it? Or is it just that no one has had the inclination to pursue this?

[JSWolf]

Originally Posted by BionicGecko

Thanks Jon, Amazon indeed does.

I guess I was more looking for a technical reason, seeing that we both have a working jailbreak and the source code. I’m not a very skilled developer myself so clearly I’m missing something

Is it perhaps that the available open source code only cover part of the kindle OS, so a fully functional .bin image cannot be built from it? Or is it just that no one has had the inclination to pursue this?

At the beginning, Amazon was a lot more open. Calibre was able to access the Kindle database and collections could be managed with Calibre. But the problem is that too many people screwed up their Kindle. This meant that a lot of people were calling up Amazon ask for help. So Amazon decide to avoid this going forward and lock up the Kindle software.

[Bluebotlabs]

Originally Posted by BionicGecko

Thanks Jon, Amazon indeed does.

I guess I was more looking for a technical reason, seeing that we both have a working jailbreak and the source code. I’m not a very skilled developer myself so clearly I’m missing something

Is it perhaps that the available open source code only cover part of the kindle OS, so a fully functional .bin image cannot be built from it? Or is it just that no one has had the inclination to pursue this?

The parts of the Kindle that handle gestures like that are not global, so the way it works is there are seperate "apps" of sorts for each state

There's a "home screen app", a "reader app" and even a "notebook app" (for the scribe, but that one is pretty integrated into the home screen one)
Whilst it could be theoretically possible to modify, say, the home screen code, unfortunately, since it now uses WASM it is extremely difficult to reverse engineer.

Basically, we don't have the source code for what we need to modify, and decompiling it does not give you the original source code, but rather, a highly obfuscated low-level language, which whilst easier, is still extremely difficult to understand

[BionicGecko]

Originally Posted by Bluebotlabs

The parts of the Kindle that handle gestures like that are not global, so the way it works is there are seperate "apps" of sorts for each state

There's a "home screen app", a "reader app" and even a "notebook app" (for the scribe, but that one is pretty integrated into the home screen one)
Whilst it could be theoretically possible to modify, say, the home screen code, unfortunately, since it now uses WASM it is extremely difficult to reverse engineer.

Basically, we don't have the source code for what we need to modify, and decompiling it does not give you the original source code, but rather, a highly obfuscated low-level language, which whilst easier, is still extremely difficult to understand

Thanks Bluebotlabs for the detailed explanation, much appreciated