Guest mode and signing in with Google in DeDup 1.5.3 on Android

In DeDup 1.5.3 on Android you start from a login screen with two choices: "Sign in with Google" and "Try scanning as guest". Guests can scan and look at results. Deleting and merging need a signed-in account.

What guest mode is

• Tapping "Try scanning as guest" marks the session as guest and shows the name "Guest". No account is created in the login code.
• The guest flag is held in memory only. The code comment says it resets when the app is killed. On the next launch, the splash screen sends you to the login screen again unless a signed-in Firebase user exists.
• The dashboard shows a "Guest mode" banner: "Sign in to delete duplicates and merge contacts", with a Sign in button.

What guests can't do

When a guest presses one of these buttons, DeDup shows a "Sign in required" dialog instead: "You're browsing as a guest. Sign in with Google to delete duplicates and free up storage." On the dashboard search, the dialog is titled "Sign in to delete". The checks are on:

• Image Scanner: Delete selected, Auto Clear and the single-photo delete.
• Video Scanner: delete selected.
• Smart Cleanup: delete selected.
• The cleanup lists on the Files tab, and the PDF and APK scanner: delete.
• Social Media Cleaner and WhatsApp Cleaner: delete.
• Empty Folder Remover: delete folders.
• Contact Deduplication: merge.
• Deleting a file from the dashboard search results.

I found no guest check on scanning, on viewing results, on the Trash screen, or on sending feedback from Settings.

What signing in does

• The login screen offers Google only. The sign-in code needs a network connection, Google Play services and a Google account on the phone, and shows a message if one is missing. The sign-in manager contains other methods, but the login screen doesn't offer them.
• Once you're signed in, the splash screen skips the login screen on later launches while the account is still signed in.
• The delete and merge buttons above start working. Signing in doesn't change how scanning finds duplicates.
• Deletion still goes through Android's own delete prompt, as in any other case.

Account data

• Firebase Authentication stores your account. The privacy policy lists your name, email address and an account ID.
• The app also saves your display name, email address and profile photo address in encrypted preferences on the phone, and shows them in the side menu and dashboard.
• Signing in or choosing guest sends an analytics event with the method: Google or Guest.
• Feedback you send carries your account ID, or "anonymous" if there isn't one.
• Settings has Logout. Under Account, a Delete Account button appears for a real (non-anonymous) account. The code asks you to confirm with Google again if Firebase needs a recent sign-in. The dialog says files on the phone aren't affected.

Scope of this post

Checked against: DeDup 1.5.3 source code (Android).

Not tested on a device: the Google sign-in flow, the guest dialogs, logout and account deletion. I didn't check whether logout clears the saved name and email on the phone. The list of guest checks comes from searching the screens for them, so a screen I missed could differ.