Protected Columns
Keep unused columns in your sheet secure
To learn more about keeping your app secure, read the latest information in our Security Center.โ€‹
When we build a screen with the data in our sheet โ€“ we donโ€™t always use all of our sheetโ€™s columns. However, your app can still download the data in unprotected columns โ€“ even if they are not used or are hidden by visibility conditions.
If you have unused columns with sensitive or private information and your app is on a paid plan โ€“ you should make those columns protected columns.
When a column is protected, none of the data in that column can be downloaded. In the Data Editor, the columnโ€™s contents will be hidden and canโ€™t be processed in any way by Glide.
Mark as protected

Writing data to protected columns

However protected columns can be written to โ€“ so if youโ€™re using a Form or an Add screen โ€“ user will be able to submit data to that column โ€“ but once itโ€™s been added, it will no longer be accessible.

Unused sheets

If you have entire sheets that are not used at all by your app then you donโ€™t need to protect them. Your app can only access sheets that the app uses.
For example โ€“ this Spreadsheet has four sheets, but the app only uses data from two of these (highlighted in blue). Because of this โ€“ our app will not download the data from any of the unused sheets.