nopCommerce is an ultimate solution for all Ecommerce needs !

• Very flexible design which is responsive to adapt to tablets and other mobile devices
• It is the only open-source e-commerce solution with multi-vendor and multi-store features!
• Supports different types of products: regular, clothing (with sizes, colors, materials, etc), configurable with features and options, bundles, subscriptions, for rent, memberships, downloadable, etc.
• Powerful catalogue tools. Define more than 60 different properties for a product like name, descriptions, prices, special prices, specifications, attributes, SEO data, stock management, etc. All of these properties are quite complex themselves so that you can achieve almost any Ecommerce scenario
• Flexible pricing, promotions and discount system with coupon codes
• Full of marketing tools such as banners, topics, best-selling and recently viewed/purchased products, up and cross sell, newsletter, reminder and notification emails, social networking (Facebook, Twitter, Google+, etc.), reward points, affiliate program, etc.
• Advanced SEO management for all catalogue pages, as well as any other page in nopCommerce. There is a backend management of all the SEO meta tags for every entity in nopCommerce. All URLs are SEO-friendly, referred to as slugs
• Compatibility with shipping providers like UPS, USPS, FedEx, etc.
• A variety of payment providers like PayPal, PayU, etc.
• User management with Vendors functionality. Define user roles, vendors and edit access control lists easily from the administrative panel. The public side is also very resourceful
• Built-in blog, news and forum with mighty tools of SEO optimization
• More than 1,000 plugins and themes offer additional options and features
• Customer service: order attributes, returns, order and requests status notifications, private messaging, automated mailing, etc.
• Supports product export to Google Sell, Amazon and Facebook
• Smart Multi-language support out of the box with an RTL support. Note that multi-language pages will not harm the SEO-optimization
• Easy & secure checkout process which integrates both with the user management and the payment providers
• Find all of them explained in details on features page