Yes, AWeber has an API, allowing customers to easily connect their AWeber accounts with other sites and services online. AWeber users don't really need to interact with the API itself at all - you can simply use AWeber apps that developers have already created.
If you are an AWeber customer, you will not need to interact with the API directly - you'll just install and use the apps that developers have created. For instance, to use the AWeber Webform Widget for Wordpress, you just install the plugin on your Wordpress site and use it from within your Wordpress control panel.
Authorizing applications designed to work with AWeber should be explained by the site or person that provided that application. If you do run into any trouble with the process, or have any questions about authorizing applications to be able to access your account, take a look at this article.
As with using applications, deactivating them will mostly be a matter of either changing the settings of the application on the site that offered it to you in the first place, or simply uninstalling the app. For information on completely removing connections to your AWeber account, read our knowledge base article on the subject.
The App Showcase
If you click the "My Apps" link in the upper right of your AWeber account, you'll be taken to our "App Showcase."
Here you will see apps that we have highlighted, either because we developed them, because they've been very popular, or because they're just plain cool. After clicking on any app listed, a brief description is provided as well as an "Enable" button allowing you to start using the app.