World.db - A Free Open World Database and Schema
github.com
github.com
It is indeed extremely incomplete.
Is that too restrictive?
For someone who doesn't want to have a "credits" page in their app, sure.
Also, please teach him something about database normalization. e.g. capital should not be a flag of cities, but a foreign key of regions and countries. Cities, Regions and countries should be combined into one table, with a foreign keys pointing up and down the chain, from world down to suburb level.
See my issue report: https://github.com/geraldb/world.db/issues/1