Newham launch of NHS Covid 19 Test & Trace app

Everyone in Newham has been sent a letter explaining about the app and a code to download. I got mine this morning. It took me about 2 minutes to install (make sure you download the NHS covid 19 app and NOT the normal NHS smart phone app) and already it tells me that my post code is "LOW risk"; my contact tracing is is active; how to check into venues; report symptoms and read the latest advice.