Elevation Logger

Elevation Logger is a prototype app which is part of my masters thesis. The overall goal is to provide elevation data to OpenStreetMap while preserving the users privacy.

Using this app your smartphone will record GPS traces and air pressure data. Using an internal OSM map we calculate the altitude differences of neighboring OSM nodes.

The data that leaves your phone is a list of tuples that each contain a "source node" a "destination node" and the altitude difference between these nodes. This data is split into Secure Multi Party Computation shares and sent to three privacy peers which each cannot see your data, but can do computations on it.

After a k-Anonymity whit intersecting traces is established on the privacy peers, the traces are released to a collector that uses the gathered altitude differences.

Unfortunately, your smartphone is required to have an air pressure sensor for this app. If you are not sure, just install the app, it will tell you if you have one ;)

This app is in experimental status and I thank you a lot that you want to participate, and help me evaluating me system!