Gmail App: Productivity at your fingertips with rich text formatting and instant RSVPs
Rich Text Formatting
Now you can add bold, italic, underlined, colored and highlighted text to your email—all from inside the mobile app. These new options are great for making a point or emphasizing what’s important.
If you use Google Calendar or Microsoft Exchange, calendar invitations now include a one-tap option to show your schedule and respond. No more opening up separate apps just to see if you can squeeze in a meeting.
Source: Official Gmail Blog: Productivity at your fingertips with rich text formatting and instant RSVPs