Square, the mobile payments company, has just released an update to its popular universal app. Square 2.0 is available now and includes a number of customization features, particularly ones for the iPad.

The app, which made a splash when it debuted in 2010, allows anyone to accept credit card payments on their iDevice without a contract or monthly fees. It recently received Apple’s seal of approval when the Cupertino, California-based company began selling Square’s required device ($9.95), which connects to the iPhone or iPad.

The app also received strong kudos from Steve Jobs at this year’s iPad 2 launch event.

Square 2.0 allows users to arrange their items into shelves on the iPad, which makes for easier browsing and faster checkout.

Also included for the iPad are different ways of categorizing items. Called “variations,” items can be arranged by “Small, medium large; chocolate, vanilla, strawberry.”

In addition, the iPhone view is now more refined and professional looking, which is a nice touch.

If any of our readers have used Square 2.0, please let us know by using the comments below.

In the meantime, get the free Square 2.0 in the App Store.