In my head there has been around a lot of times the possibility of contributing to the OSS community with some gem, so here goes my first contribution there. Localio is an automatic localizable file generator.
It reads a certain type of file, called Locfile, and process it so the different localization files for your app are automatically generated. Android, iOS, Rails and JSON are supported now. The localization information is processed from a Google Drive spreadsheet or a local excel file. Those spreadsheets must have a specific format for this to work, though.
An example of Locfile:
platform :ios output_path 'Resources/Localizables/' source :google_drive, :spreadsheet => '[Localizables] My Project!', :login => 'email@example.com', :password => 'your_password' formatting :smart # This is optional, formatting :smart is used by default.