[uhybouy]

And is very expensive and restrictive in how you can use it.

We licensed the Postal Address File (the list of official correct addresses for each house) and we had to add encryption to our product to stop people being able to extract the raw data from the code.

The same applies to Ordnance Survey map data - there are a lot of apps that aren't possible/easy in the UK because of the cost and licensing of the maps that the taxpayer paid for.