This Amazon Product Advertising library includes ApaiIO, a PHP library that fetches the API using REST or SOAP. Because of its flexibility, users can perform built in operations such as ItemSearch and ItemLookup. Or, they can include other operations that can be more suitable for a specific project. Documentation, currently under construction, is available. Installation and web usage also accessible on the site.
Involver launched its Engagement Optimization API last week (read the official release here). Partners are utilizing the API to "optimize their ad spend on social in the way they've been doing across the web for a long time." Although advertising across social networks has been deployed for quite some time, advertisers have had limited tools to track engagement. Facebook Insights is probably most commonly used to analyze social data. When users have required deeper analysis, the advertisers were forced to use highly custom integrations.