Also, i don't think that something like this is easily done
You have so much trouble combining PC parts ( that are bigger in parts and all embedded by a motherboard that doesn't even fit all of them) and putting them into a universal OS working for all(think how many drivers you need at your PC).
Now get over to the nano(micro?;?)systems mobile phones use.
Yes, it could possibly happen under a common base of operations( for example, only Samsung upgrade parts) BUT that's not Samsung(for example) wants in any case.