A very simple API that checks a geolocation of a given IP address.
Geo uses the http://www.ipinfodb.com API to check the IP address that the request comes from.
config.yml needs to contain the API key from IPInfo.com, and also, the key/value pair of what you're looking to check for.
Simply include the / route as a script (<script type="text/javascript" src="http://www.mydomain.com/?callback=myJsFunction"></script>). For the callback parameter, use a Javascript function name of the function that you want to handle the result. What will happen is you will get back a true or false as the first parameter.