When using the calendar synchronization function, you should pay attention to the following key points: iOS 14 or above is required for the device, and you need to keep the VPN open (in some areas) to synchronize with Google Calendar. At the data preparation stage, you should ensure that the photographic materials contain complete time information (avoid relative date expressions such as "next Wednesday"), and we recommend that you give preference to promotional materials with a clear date format (e.g., 2025-08-15) and a 24-hour time system.
There are two stages of verification in the synchronization process: firstly, the app will mark fields that are not identified with certainty (e.g. location identification due to fuzzy pictures), which requires confirmation from the user; and secondly, there will be a secondary check for time conflicts (e.g. duplicate addition of same-name events) when writing to the calendar. Apple Calendar uses system-level direct synchronization, while Google Calendar requires OAuth 2.0 authorization (login for first use).
The privacy protection mechanism is reflected in the fact that: all picture analysis is done on the device side, and only the final calendar data (encrypted with TLS 1.3) is transmitted from the cloud; the user can revoke photo/calendar permissions of the app at any time in the system settings. The developer declares that the original images and recognition intermediate data will not be stored, and all caches are automatically cleared when the app is deleted.
This answer comes from the articleSnapCal+ BOYK: Take a photo to automatically extract event information and add it to the calendarThe
