Designed for Use, 2nd Edition

Provide an API and a Plug-in Architecture

You don’t have to implement every feature on your own. Often, it makes sense to let others chip in and help. Twitter, for example, started out with an extremely simple service. But its API^[122] allowed other developers to step in and create a whole ecosystem of great products that revolve around Twitter. Photoshop is another great example. Although Adobe has added an incredible number of features to Photoshop, it couldn’t possibly implement every feature that its customers might want. Instead, Adobe allows third-party developers to create plug-ins for Photoshop, thus broadening the market for the product without investing any of their own money or making Photoshop even more complex than it already is. ...