Shopify is a flexible, feature rich, hosted and managed ecommerce platform that makes it easy to sell and deliver your products to your customers.
FetchApp works by connecting with existing shopping carts to deliver your digital products. We integrate with a variety of popular shopping carts to make the sales and delivery experience easy for you and your customers.
WooCommerce is an easy-to-use shopping cart that is built on WordPress. It can be integrated with a variety of plugins to make selling your products easy. 
PayPal may be the easiest way to get set up accepting payments on the web. With FetchApp and PayPal, you can start selling your digital products immediately with just a little copy and paste.
Joomla! is a powerful content management system. Nikita Zonov from http://joomalungma.com has released a free Joomla extension for FetchApp. You can download the extension and watch the tutorial here.
Foxycart delivers a superior ecommerce experience for developers, merchants, and shoppers. Foxycart offers powerful tools to increase conversions and help merchants increase sales.
FetchApp offers an API to help you with custom integrations either with one of our established shopping carts, or one of your choosing. With our API, your options for integration are virtually limitless.