George McKernon sent details of a joint project he is involved in at LSE called 'mappiness'. It's a free iPhone app that rather simply implements the Experience Sampling Method, including use of GPS (linked to environmental data using GIS at the analysis stage).
Mappiness is now live, with its own website: http://www.mappiness.org.uk/
They would be very grateful for any feedback on the website, the app, and/or the broader methodology. His website is below.
George MacKerron | http://personal.lse.ac.uk/mackerro/