The row between a Swiss-led consortium and a German-led consortium about the right approach for a European contact tracing app has been resolved with Germany falling in with the Swiss model.

The row was over where information generated by the app should be stored. 

Germany’s PEPP-PT system stored it centrally, Switzerland’s DPT-3 system stored it on the mobile device.

The Apple-Google system also stores it on the device.

All the systems use Bluetooth-based smartphone contact tracing which assesses the closeness and length of contact between people and, if someone  tests positive for corona, tells recent contacts to call a doctor, get tested or self-isolate.

Under DPT-3, the information is not sent to government, and users have the option of of whether  to share their phone number to aid contact tracing, or not.

If they opt in to sharing then they can exchange information with other app users.

DP-3T stands for Decentralised Privacy-Preserving Proximity Tracing.