Apple has gone live with a feature to transfer photos and videos from iCloud to Google Photos. It seems that in the future it will also be possible to migrate other data to other services.
The feature only works one way, so the photos and videos can go from iCloud to Google Photos, but not the other way around, according to the help page about it. The transfer is not a quick process: it can take between three and seven days, Apple notes. The photos and videos will remain in iCloud storage after the migration.
To transfer, users must submit a request to Apple through the Apple ID Privacy page. Apple warns that users must have the necessary space at Google, but cannot check that. When the space runs out, copying the files will stop.
The feature is live for users across the European Union and some other European countries. It therefore seems that the function stems from European regulations regarding data portability; users should be able to transfer their data from one service to another. It is unknown whether the export function will also be available outside of Europe.