You can get it one of two ways:
- Use the Connect IQ SDK Manager in Eclipse, by clicking the Connect IQ menu, selecting Open SDK Manager, and then clicking the Download button for Connect IQ SDK v2.1.2 released August 9, 2016.
- Download directly from our developer site at http://developer.garmin.com/connect-iq/sdk/
There are all sorts of new features available in this release of the SDK, many of which are highlighted here: http://developer.garmin.com/index.php/blog/post/connect-iq-2-the-biker-has-arrived. View the README included with the SDK for a full set of release notes!