- Gmail (and its offline companion)
- Outlook
There is also a built in terminal (named Crosh) that you can access using CTRL+ALT+T.
- Google Calendar and its extension
- Spotify (and hotkeys extension)
- Google Drive
- Google Photos
- Dropbox (and its FileSystem extension for the ChromeOS file manager)
- OneDrive (and its FileSystem extension for the ChromeOS file manager)
- Box
- Chrome Remote Desktop
- TeamViewer Web Client (free for private use)