No roll-out date set for the new collaborative contact tracing app

The video discusses the importance of ensuring the effectiveness of test and trace technology before recommending its use. It highlights the challenges faced in the test and trace system, emphasizing the need for public cooperation in getting tested when symptomatic. Additionally, it provides an update on the shielding program, indicating that changes will be communicated to individuals through letters from the NHS.

What is the significance of the individualized letters mentioned in the text?

What are the two symptoms mentioned that should prompt individuals to stay at home?