On the PPI framework blog there's a recent post showing how to use the framework to create geolocation functionality via an interface with FourSquare and Google Maps.

In this article, we're going to learn how to work with the framework as a whole by writing a real-world application: making a module, controller, routes, templates (views) and services. In order to achieve this we are will use the Foursquare API, and APC for caching the API lookups. We will plot venues from Foursquare in Google Maps for display.

They help you set up a skeleton application and start on creating the "Foursquare Module" along with its controller and views. There's Javascript code included to use the Google Maps functionality and a simple class to work with the FourSquare API to get nearby venues. In the end, you'll have a basic application that maps out the points automatically.