Google has added a few minor adjustments to the calculator application in version 7.3 which it seems is being pushed out as an update to the Play Store as of today or fairly recently. That being said the update may not make its way to everyone right away and it could take a few days before it shows up for all users. If you use the calculator often enough or just want the latest version of the app without having to wait, you can also grab the APK for version 7.3 from the button below and install it onto your device, though if you don't mind waiting for a Google Play version of it the update shouldn't be too far off if it hasn't already shown up.
As for the changes, version 7.3 comes with a slightly new icon for the app that you'll see in the app drawer and for the shortcut to the app that you place on the home screen. The icon isn't too different from the one that can be seen currently for those who aren't on the latest version, though it is a noticeable change as the "=" symbol used to be contained within a circle in the bottom right corner of the icon, and now it's simply contained within the initial square icon shape with the rest of the symbols. This of course doesn't change anything functionally but it should keep things streamlined with the rest of Google's icons and follow along with the same design language.
So far it seems that there is only one or two functional changes to be found within the app itself, the first of which is a little arrow icon on the bright green bar that sits off to the right part of the app UI to denote that there is a slide out menu that can be accessed. Prior to this version the menu was present but you might never know it just by looking at the UI, so now it should be much easier for users to locate this menu. There is also now an ability to edit the text for characters in the value field (the white box at the top of the UI), so if for any reason you need copy and paste or move around any parts of the text you can long press on the values that have already been entered just like you could with text in any other app and you'll see the options for copy, paste, and cut the text, and if you select all of the values to highlight them you get the ability to access a select few memory actions like MS, M+, and M-.