eBay is working on services that will give buyers and sellers new tools - such as a shopping cart, further item information, and more fixed-price options - on the online auction site.

For external developers the company will release new APIs (application programming interfaces) to enhance eBay-based applications aimed at online buyers. The company is set to announce the APIs today at its developer conference in Las Vegas.

eBay expects the APIs to be particularly attractive to its third-party affiliates, which feature eBay listings on their websites and get rewarded for sending traffic to the eBay marketplace, said Greg Isaacs, director of the eBay Developers Program.

One new API will allow affiliates to provide more information about products listed on eBay, theoretically increasing the likelihood that their website visitors will click on the listings.

Another API will let them fine-tune the listings displayed on their websites if they have blogs or content that is often changing.

Two other APIs are focused on the company's recently launched eBay Express website, which features new, fixed-priced items aimed at a more mainstream buyer than the traditional auction-loving eBay user.

One will let affiliates limit the listings their visitors access to eBay Express items, filtering out other eBay inventory, such as used items and those available on auctions.

The other API gives developers access to the eBay Express shopping cart, letting buyers add items from multiple vendors. Prior to eBay Express' launch, eBay lacked a shopping cart.

Meanwhile, eBay's PayPal online payment unit will improve the web support for its developers, launching a community site and revamping its developer hub.

The PayPal Community site will feature discussion forums and blogs, so that they can communicate with PayPal experts and other developers. Meanwhile, all developer resources will now be centralised in the Developer Hub along with access to an Integration Center that contains product documentation, APIs and SDKs (software development kits).

Improving web support for developers is key as PayPal grows its base of developers beyond the eBay marketplace, which has been its main market traditionally, said Tim Villanueva, general manager of the PayPal Platform and Developer Network. This "off eBay" market for online payments is, naturally, significantly larger than the eBay market, and represents PayPal's growth focus, he said.