Android - Adding to a ROM and upgrading - Questions

** Not sure if this is entirely relevant to SO, it is programming related in nature but if its more suitable to a different forum please let me know and I will remove it **

I have a couple of questions for any Rom developers/experts on here regarding things that can be done with Android ROM's.

1) Is a parser Rom upgrade possible? So is it possible to change a small part of a ROM and then allow users to upgrade their ROM easily?

So can I change a part of a ROM and then a customer can upgrade to the newer ROM without having to be technically savvy and needing to root and flash their devices?

2) Can a change be burnt into a ROM so that when a user selects "Restore Factory Settings" that it doesn't remove the upgrade to the ROM?

3) So essentially I want to know if its possible (with a device manufacturers permission) to add to a ROM some small additional parts and then give this new ROM version as a firmware upgrade to the d开发者_开发知识库evice so that a user only has to "upgrade" and not go through the process of rooting and flashing there device?

I'm not sure, but I feel that likely what you ask makes no sense: the whole point of rooting is being able to change the ROM.

Maybe if you give more details about what you really mean to do, someone will have a workaround that will satisfy you anyway.