As noted by iMore, the free update adds secure video recording directly to Apple's Home app for users with a paid iCloud storage plan.
EufyCam 2 is one of the first security cameras to support Apple's new HomeKit Secure Video feature. Support for the feature was first unveiled during Apple's WWDC 2019 keynote, but it wasn't available when the eufyCam 2 launched last fall.
The firmware containing the support is version 2.5.9 and is currently rolling out to EufyCam 2 owners as a silent automatic update. Users can also manually check the availability of the new software via the firmware update option in the eufy Security mobile app.
The release notes don't mention the feature addition, so it's unclear whether Anker's other HomeKit camera, the eufyCam 2C, is also getting the upgrade.
According to Apple, HomeKit Secure Video is only available to users that pay for 200GB or more of iCloud storage, starting at $2.99 per month. Users with the 200GB plan can store 10 days of recordings from one camera in iCloud at no extra cost, while those with a 2TB plan can store 10 days of recordings from up to five cameras. HomeKit Secure Video recordings do not count towards a user's iCloud storage usage.
Update: A spokesperson for Anker informed the blog iPhone in Canada that the rollout of HomeKit Secure Video for the EufyCam 2 has been delayed until mid to late April.