Gmail is a pretty successful product, obviously, and when you couple it with Google Chrome you can make it even better. There are a bunch of extensions out there for Gmail. Chances are you can find what you are looking for. These are the three that I like the best, and use the most:
Just a note, I do not believe any of these work with Google Inbox.
The Top Inbox for Gmail
This performs quite a few features for you but the two I use the most is the ability to schedule an email to be sent at a certain time and the ability to see if the email was opened or not (better known as a read receipt). All you have to do is install the extension and then when you open Gmail and create a new email message you will notice a little toolbar at the bottom.
Ever have to send the same email to different people? This makes that task a little easier. You can create a template – give a shortcut word and then type that word in your email message and hit the tab key. Bam! Your template will populate the message.
Gmail offers a bunch of ways to customize your email, but sometimes, just sometimes, you will want to embed something in the email. There is no way for you to currently do this in Gmail so in comes this little guy. It allows you to view your email in HTML and then make changes. Now Gmail does strip out some code regardless of how harmless it is. Yet, I still have found it helpful for embedding instructions or other content into the email.