Avactis is a powerful PHP shopping cart application that has multiple versions (including free + open source) and impressive features.
It has everything and more to expect from an e-commerce tool on every level from product to member managements, orders and marketing.
Unlimited categories and products with any number of images (auto-thumbnail support) can be created. Using "custom fields", you can better define a product and help users reach to it with a point-shot search.
The application is very flexible in creating any type of promotions like discount codes, price-based or quantity discounts discounts, built-in affiliate system, newsletter management and more.
SEO is taken care of -mostly- automatically with SEO-friendly URLs, optimized HTML code or breadcrumb navigation and more can be done with the help of custom meta information and titles.
Avactis works with almost every popular payment processor including PayPal, Google Checkout, Authorize.net and much more.
When it comes to frontend, the look and feel can be totally customized via CSS and templating system.
A CSS Editor, which actually works like a site builder, helps switching between styles and designing the storefront while browsing it.
Modules like featured products, newsletter subscription, registration can be positioned with a "Visual Layout Editor".
Simply, Avactis is a complete software for creating and managing an online store. And, besides the paid ones, it also has a free version.
The giveawaySitepoint and Avactis are running a giveaway of 50 Avactis full licenses with Brandon Eley & Shayne Tilley's "Online Marketing Inside Out" (Online Marketing: Sitepoint) book. You can join it from the link above and act fast as it'll be expiring soon.
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