1. Gmail Offline allows you to disconnect from the Internet so you can focus on your inbox.
2. Smartr Inbox for Gmail shows social media accounts of the people who email you, so you know the latest about them as you reply.
3. Google Tasks is built into Gmail and Google Calendar, but this extension makes it more accessible and easy to use.
4. Grammarly Lite checks spelling and grammar as you write.
5. Email this page (by Google) lets you quickly email a website or highlighted portion to someone.
— Adapted from “100 Chrome Extensions that You Should Install,” Trevor Dobrygoski, Lifehack.