The Free Geolocation API returns IP information with no registration required. Formats available are JSON, XML and CSV. The API returns region, country, IP, geocoordinates, city, timezone, zipcode, city and more. There is a rate limit of 15k requests per hour.
The following is a list of SDKs from our SDK directory that matched your search term. Though your definition of an SDK may differ, in our world, we define SDKs as platform- specific tools for consuming existing APIs of the sort we list in our API directory. For example, the Ruby SDK for consuming the Twitter Ads API. If you think an SDK, API, or other asset is missing from our directory, be sure to check our guidelines for making contributions to ProgrammableWeb.