If you don't need street-level geocoding, the GeoNames [0] project providers their data free of charge (attribution required). It provides city and district level data, which is suitable for tasks such as displaying the location name of photos or rental listings.

Self plug: I wrote a Node library a few years ago to use this data offline. It builds a SQLite database, which is small enough to be suitable for embedding into applications. [1]

[0] http://download.geonames.org/export/dump/readme.txt

[1] https://github.com/lucaspiller/offline-geocoder