As of 2015, Math-Play.com and MrNussbaum.com offer practise on a virtual cash register. Both websites contain games that enable users to conduct free online cash register transactions. Math-Play.com also offers an iOS app for a cash register.
Click Money Games near the centre of the homepage and then Counting Money Game to use a virtual cash register on Math-Play.com. Click the Play button to begin.
To practise using a virtual cash register on MrNussbaum.com, click Search this Site, enter “cash out” in the search area, and then click Cash Out on the following page. Click the Play button to begin.