The European Commission issued a statement to harmonise an approach for safe and efficient use of contact tracing apps across the EU. The commission stated that voluntarily installed tracing apps can contribute to the gradual lift of travel restrictions, combined with traditional tracing and other efforts such as increasing testing. It underlined that tracing apps must be 'voluntary, transparent, secure, interoperable and respect people's privacy'. Furthermore, no geolocation or movement data should be collected, and data should be anonymised. The statement also urged all apps to only be used temporarily and to be deactivated once the public health emergency is over. Interoperability of apps was stressed as it is crucial to relax confinement measures and lift movement restrictions throughout the EU, while enabling the tracing of cross-border infection.