Still using a clunky cash register? Now you can ring up sales, generate receipts, and track inventory wherever you go using Web-based point-of-sale software. The systems work on any computer with Internet access, including tablets.

This easy-to-use software lets you perform a variety of tasks, including ringing up sales, managing inventory, and generating real-time sales reports. Like the other applications mentioned here, it works with peripherals such as cash drawers, bar-code scanners, credit card terminals, and receipt printers. A subscription to the service includes a full-featured iPad or Android app. cost: Starting at $70 a month for two registers, two users, and up to 50,000 inventory items

Like Erply, this cloud-based software lets you ring up sales, manage inventory, and generate sales reports. It also lets you send receipts with links to your company's Facebook, Twitter, and Foursquare accounts to customers via text message or e-mail. You can also use Pose, which has an iPad app in the works, to create an online store using a template. cost: Starting at $50 a month for one cash register, one user, and unlimited inventory

ShopKeep offers a dedicated iPad register for retail shops with fewer than 270 items, as well as systems for Macs or PCs tailored for larger stores. Users with premium accounts can launch an online store through As with the other software here, the ShopKeep register still works if the Internet is down. cost: Starts at $49 a month for an iPad app with one register, unlimited users, and fewer than 270 items