ganeshdole

Definitely! I can improve the UI and add more filtering options.

As per my knowledge, Android allows us to root our phones and gain system access. But they don't allow us to do such as payment processors and authentication services.

user security concerns?

I am not asking if it's possible to build such a thing. I am asking if you're interested in a phone that you can customize to your own needs.

Why is it necessary to standardize the hardware market? Can't we simply build our own hardware?

Yes, that's what I am saying, I don't use my phone camera, instead, I will replace that part covered by the camera with more battery or CPU. As for the operating system, you can choose the OS you prefer - whether it is rootable or not, or even your own custom OS

Like having physical switches to control GPS? But, Most operating systems such as IOS and Android offer built-in options.