For one research project, hundreds of test subjects were given mobile phones on which a special was installed. software that collects data on the level of noise, light, motor activity, etc., and sends them to the server. The data are identified by the IMEI code of the device from which they came.
It is necessary to organize the entrance to the site for the subjects, where they will be able to see some statistics on the data collected from their device.
The study is anonymous, and I want to avoid collecting any data such as email. mail or phone numbers. It happens in Europe, then the hellish laws to that effect. Even if all the subjects are “their own” :)
What is the best way to organize authorization / login to the site, without registering users, but based only on the fact that they now have this device?
While the only option is to force the mob. developers add a function to the software so that it generates a temporary token, for example. MD5 dates and IMEI device, and the server would check it (and + - 1 day for each). Those. I got the phone, opened the program, entered a temporary token - entered, saw my statistics.
How would you do this better and wittier, without finalizing the mob. customer?