Adding shipping and posting functionalities to your applications may be necessary for your what you're trying to achieve, but it may not always be a quick and easy process. EasyPost is a posting and shipping service specifically designed for applications, saving developers some very valuable development time. The EasyPost API makes it possible for developers to access this functionality and easily integrate it with other applications.
Our API directory now includes 32 postal APIs. The newest is the Stamps.com API. The most popular, in terms of mashups, is the GeoNames API. We list 84 GeoNames mashups. Below you'll find some more stats from the directory, including the entire list of postal APIs.