Google announced that it has updated its iOS app, after the app faced a great amount of criticism following its initial launch.

Google had gone without offering an iOS app until just last month. The concept was greeted rather warmly by iPhone and iPad users, but the product not so much. It was full of bugs, but Google did launch an update shortly thereafter.

That didn’t curb all of the criticism, but that’s virtually impossible anyway.

Anyhow, today they’ve announced a new update.

With the new version, Google has added the ability to set custom signatures for mobile messages and vacation responders. These can be accessed through the gear icon at the top of the menu view. They also added improved labels with support for nested labels.

There is new notification sound for iOS 5 users. Google says it makes it easier to distinguish when you’ve received an email.

You can now open up a canvas and scribble messages that will be attached to emails. The feature, also available from Gmail for Mobile, supports different colors, brush sizes, lines, erasers and spray paint.

“It’s perfect for sending a quick sketch that is hard to express in words or adding a fun graphic to make your email more personal,” Google says in a blog post.

The company says it is also continuing to work on other highly requested features like banner notifications, multiple login support and the ability to send as from any account.

The new update is for iOS 4 and up.