Google may have announced the impending shut-down of Google Labs, but Gmail Labs is still putting out new optional features for Gmail users.

Google has released the “Preview Pane” as a Gmail Labs feature. This allows users to preview messages in their inbox using a layout similar to how Gmail looks on a tablet device.

“When I check my email, I often rely on the message snippets to figure out which messages to open first,” says Gmail Associate Product Manager Maciek Nowakowski. “Sometimes, though, I want to see more than snippets, which is why I’m happy to announce that you can now preview messages in your inbox using a new feature in Gmail Labs called Preview Pane.”

Like all Gmail Labs feature, you have to enable it in settings. Once you’ve done so, you’ll see a toggle button in the right corner of your message list. This lets you switch between preview and list views. The button looks like this:

“For those of you who have more vertical space you can also move the preview pane below your message list. You can enable this using the dropdown arrow next to the toggle button,” notes Nowakowski. “By default there is a 3-second delay in marking a conversation as read after previewing it. If that doesn’t feel natural to you, you can change the timing in the General tab of settings.”

Google also announced the expansion of phone calls from Gmail earlier this week. Last week, they showed off a script that lets you hit the snooze button on email messages.