How to install inbox in my Samsung 13 phone?

What folder(s) ''do you see'' in the mobile app? Do you have more than one account and perhaps looking at the unified inbox? # Press the top left button to show the side menu. # Tap the down arrow and select your account. # This should display a list of folders (Inbox, Trash etc) If your account uses oAuth 2.0 authentication, did you complete the oAuth sign-in process during setup? Imap folders will not display until the app has successfully signed in to your email providers server. # Navigate to settings > account name > fetching mail > incoming server. # Tap the next button (This will test the connect to the server) # OAuth Flow: Tap the Sign-in button (if displayed / prompted) If sign-in is successfull but Inbox still doesn't display .. # Open the side menu with your account folders visible. # Tap manage folders (bottom of list). # Tap three dot menu > refresh folder list. # Tap Inbox. # Check "Show folder" is enabled. Note: This forum is focused on the mobile app. Questions related to Thunderbird desktop are best posted in the [https://support.mozilla.org/en-US/questions/thunderbird desktop forum] where members with knowledge of that platform can assist you.