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Comment by vageli | Hacker News Reader

I would love to learn more about the reverse engineering process for a bluetooth device like this. It's too bad there is no link to a blog or additional documentation in the repo.

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You can decompile android apps, which will give mostly the original Java Classes / functions with anonymized names (class A, function b, etc...). Framework classes and methods usually stay pretty much the same.

See for example https://github.com/robertohuertasm/apk-decompiler and https://github.com/vaibhavpandeyvpz/apkstudio (only used the first one but the seconds looks practical)

The repo states that they reverse engineered the Android app. So potentially 0% BLE specific reverse engineering and 100% of android Java. In some cases reverse engineering java code, which decompiles relatively well, can be easier than trying to sniff bluetooth packets, potentially dealing with standard bluetooth encryption and guessing what the raw bytes do.

Can confirm, reverse engineering Android apps is decently easy if you aren't afraid of manually parsing Java bytecode (it's not that bad). I tried to reverse engineer the encryption/decryption mechanism for a digital book app (it was garbage, and I just wanted to read my books in a nice app :( ) and was almost successful.

You can buy a Nordic Semi usb devkit and their software can sniff. Maybe you can have the Android sw run in a virtual device and catch api calls

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