New answers tagged google-sync
In the end it turned out to be a blogger.com blog storing photos in the Google Photos account. We had assumed the blogger account would use it's own photo store. Bottom line: Google uses Google Photos for general photo storage for many of its services.
For me the solution was, that some gmail calenders were synced and some not. I found out that you have to check if they are marked for sync within gmail or not. For that purpose visit: https://www.google.com/calendar/syncselect and check if your problematic calendar is marked for sync or not. By default, all of your own calendars and birthdays are enabled ...
Google + for iOS, Google Photos for iOS and Google Photo Autobackup do that. The age of the pictures is not really relevant, because the last app would upload any image on your computer (on the pictures folders mostly). Also, Picasa used to be able to sync your pics with G+, although I'm not sure it was automatic.
You could use Box. To my knowledge, they used to offer this feature.
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