Amazon.com Inc. on Friday said it had extended its development tools to developers looking to link their applications to Amazon's websites for Canada and France.

The announcement means all six Amazon-branded sites worldwide are now supported by the company E-Commerce Service, which includes documentation, code samples and sample applications for developers.

Through the ECS, web site developers, or their employers, can earn a referral fee when users of their sites make purchases on an Amazon site. For sellers on the Amazon Marketplace, the tools enable pricing updates for products and other capabilities.

Developers can also build and sell Amazon-related applications to other websites.

Amazon shipped ECS 4.0 in October. Among the new features in the upgrade were detailed attributes and pricing on tens of millions of products in all categories, access to Amazon's customer reviews and massive image collection, and search by numerous attributes, including brand, price and category.