I'd like to encrypt an existing file using the Android app. In the Windows world, I can go to the file in the X: drive, right-click and go Boxcryptor -> Encrypt to encrypt the file. In the Android world, I was hoping to go the file in the Boxcryptor app, tap the 3 dots for actions and find an "Encrypt" entry there. But all I see are "Share", "Delete", "Rename", "Copy", "Move", "Download", and "Make Available Offline". No entry for encrypting the file. Am I out of luck?