What are some alternatives?
When comparing ipgeolocation.io and Ipregistry, you can also consider the following products
ipstack - ipstack is a free, real-time IP address to location JSON API and database service supporting IPv4 and IPv6 lookup.
ipinfo.io - Simple IP address information.
IP-API.com - Free IP Geolocation API - lookup any IP address
ipdata.co - Get the Geolocation, Organisation, Currency, Timezone, Calling Code, Flag, Proxy, Tor and Threat intelligence data from any IPv4 or IPv6 address.
Geo IP Tool - Find a geolocation of an IP address including latitude, longitude, city, region and country.
IPTools - The "IP Tools" is powerful and handy application for network analyzing.