Google has introduced Confidential Mode to its Gmail application, allowing users to passcode-protect their communications and set expiration dates for both email content and attachments. The feature was initially announced during Google's I/O developer conference earlier this year but had remained mostly out of the news in the meantime. In short, it enables users to set a time limit within which an email and any attachments to it much be handled by the message's recipient before it effectively self-destructs. Of course, the feature is only available in the latest iteration of Gmail and is currently limited to mobile devices, meaning it won't be accessible for those using the "classic Gmail" layout in a browser. With that said, it does disable the recipient's ability to copy, forward, or download attachments. So it should still go a long way toward keeping sensitive emails and attachments out of the hands of people they weren't intended for.
Using Confidential Mode is relatively straightforward on the sending side of the equation but must be turned on for each individual composition. In the web interface, that's accomplished via a new 'lock and clock' icon set amongst the email text formatting and attachment features in the composition toolbar. The mobile app interface hides the tool in the three-dot context menu within the app's composition page. Once clicked, users will be able to set an expiration date ranging from one day to five years. There are no custom date range settings available at this time but that hasn't been ruled out for future updates. Sender's can, however, go into the email later and revoke access early. After setting expiration, either the 'No SMS passcode' or 'SMS passcode' option needs to be selected. All passcodes are generated by Google when the message is received and the sending party is responsible for ensuring the correct phone number is entered. However, recipients not using Gmail may receive the passcode via email.
On the receiving end of the equation, both Gmail and non-Gmail users can receive protected emails. For Gmail users, emails are immediately viewable in the application but require a sign-in on the web when there's no SMS passcode required. If one is required, there will be a button to press to receive passcode and a space to enter the code in order to view the complete email. For non-Gmail users, a passcode will be required either way and will be sent via either email or SMS depending on the sender's settings once the receiving party has clicked the in-message link. There are a few limitations to the current iteration of the new tool to be aware of. Users in regions other than North America, South America, Europe, India, and Japan won't be able to receive SMS messages to unlock an email or its contents, for example. Google warns that the mode also won't stop malicious entities or the receiving party from taking screenshots, picture, or making copies of an email and its attachments. Lastly, it's not currently available for the users it would most obviously benefit – namely, G Suite customers. It will arrive on the platform at a later date but doesn't appear to be quite ready yet.