OpenWalk allows to share step count data anonymously between users all over the world. It collects data from Health Kit and sends it to the server. In return you receive global step count statistics and an indication of a percent of people that walked less steps than you. This allows you to see how well you are performing compared to the whole world.
OpenWalk will work with any step counter that can share information via HealthKit. If you have an iPhone 6 or iPhone 5s you dont need any additional software or hardware: in-build pedometer will automatically share your data with HealthKit.
OpenWalk will only collect information that you share through HealthKit. It will not collect any information that could link back to your identity. Individual data points stay anonymous, while the global statistics is available to everyone.