This looks like a very basic question.
I am unable to retrieve a few basic information like
Build.MANUFACTURER
, Build.MODEL
, and Build.V
These are obtained by the system from the file /system/build.prop
. If it's coming up as "unknown" in your code, it's because it's either not set, or it's set explicitly to "unknown".
There's not much you can really do about this, though. It's set by the manufacturer, and if they failed to do it, then it won't be set. If you're rooted, you can edit the file yourself, but that doesn't help if you're talking about other users.