The list of updates is massive, and it’s not just for the 530. If you have an 830/1030/1030 Plus they also are getting some love, but I don’t have those guys, so sorry, you’re on your own ;). Fantastically, it looks like you don’t even have to use Garmin Express to get it now, as each post (linked here) includes the download.

Changes made from 6.20 to 7.00:

CIQ:
-Added CIQ 3.2 support.
–Added encryption for CIQ widgets and data fields.
–Added CIQ data field alerts.
-Added BLE sync support for the Connect IQ app.
-Added CIQ workout information support.
Indoor Training:
-Added smart trainer widget that includes Tacx Road Feel controls.
-Fixed issues with grade, power, and resistance controls for smart trainers.
-Fixed course points for indoor trainer rides.
-Added the Virtual Partner to the map page when following course or activity on indoor trainer.
-Fixed lap banner bug on trainer grade control page.
-Improved indoor trainer workout UX.
Simple Setup:
-Added Simple Setup support. Port old activity profiles and sensors from Garmin Connect during initial setup.
Livetrack:
-Added device driven Livetrack.
-Added course sharing.
FTP:
-Improved reliability of FTP auto detection.
-Added tone to end of FTP test to notify user of completion.
-Fixed FTP test workout preview page.
Fixed crash when updating sensor software.
Fixed issue with smart eat and drink alert prompts.
Fixed segment completion bugs.
Fixed bug in Intensity Factor calculation.
Fixed retaining light network disable over power cycle.
Added instructions for pairing a radar in the radar sensor search menu.
Fixed other minor UI bugs and crashes.