Gnu describes freedom as freedom in speech not in beer. GNU/Linux on PCs had given us the freedom. But what about the mobile computing devices i.e. simply smartphones. Lets take a look at the available options:
Symbian: Used chiefly on Nokia phones. From version 9.0 onwards Platform Security has been introduced. Means a developer needs to register with Nokia to obtain capabilites to use all features of the platform. Only applications signed by phone manufacturer can be installed.
iPhone: Applications can be installed only from the App Store. Apple has the right to remove the applications from it.
Blackberry: Same story again.
Andoroid: Much hyped to be an open mobile platform. Android's source code is open to everyone, but OEMs are allowed to disable software installation at will. Link1. Link2.
In brief, all popular handset makers keep the platform locked.
I think closed source MS Windows do much better. I get a PC, purchase Windows license and I am free to do whatever I want to do with it.