It might be something more than codec, lots of people who are into audio can't tell the difference with better codec, but even normal people can easily tell samung buds sound better on Samsung phones, I think it's the same for Apple as well. Some people say they make other devices purposely sound worse and then say it's just the codec, or they apply a slight eq which makes everyone perceive them as better.

Also the battery and software part was very easy. For software I paired them to my phone and turned off touch controls because I was going to unplug the touch sensor and didn't want it freaking out, turned off transparency mode because it would freak out as well if this worked. And the battery was easy, there was a positive and negative contact pad, you have to solder the positive and negative end of the USB wire to them, the only hard part was soldering them individually and connecting them together into 1 USB port. One bud didn't work so I had to remove it and solder again until it worked.

It was a huge pain to work on it, something so small and I have very little experience and lacked the propper equipment for the job, probably the most janky soldering set up anyone has ever seen.