Geopaparazzi is a tool developed to do fast qualitative technical and scientific surveys. Its strength is its direct connection to the BeeGIS GIS, that can be used to further process the collected data. Even if the main aim is in the field of surveying, it contains tools that can be of great use also to tourists that want to keep a geo-diary.
There is a lot of info on the wiki if you need help getting the most out of it. It uses OSM maps by default and the current location can be opened in Mixare. Unfortunately, the suggested compass app is not free software.