Word by ITV News Multimedia Producer Kate Mead
The contact tracing programme was supposed to help ease the coronavirus restrictions safely and help battle infections.
Here's a timeline of the key events:
Health Secretary Matt Hancock sets a goal of reaching 100,000 tests for coronavirus per day by the end of April.
Mr Hancock announces the new NHSX app for contact tracing.
He says it is currently being tested and the government is working with world-leading tech companies and experts in clinical safety and digital ethics.
He says: “If you become unwell with the symptoms of coronavirus you can securely tell this new NHS app and the app will then send an alert anonymously to other app users that you’ve been in significant contact with over the past few days, even before you have symptoms so that they know and can act accordingly.”
Millions of people become eligible for a coronavirus test under an expansion of the testing programme for essential workers and their households, the Health Secretary says.
Mr Hancock says the government has met its target of hitting 100,000 coronavirus tests in a day by the end of April after conducting 122,347 tests on April 30.
Transport Secretary Grant Shapps says the contact tracing app will be piloted on the Isle of Wight before being rolled out more widely later in May.
As trials of the new coronavirus contact-tracing app begin on the Isle of Wight, Mr Hancock dismisses warnings by civil liberties campaigners that it could open the door to widespread “state surveillance”.
Prime Minister Boris Johnson sets a new 200,000 daily coronavirus testing target by the end of the month.
Former TalkTalk chief executive Baroness Dido Harding is appointed to lead the contact tracing programme.
England’s deputy chief medical officer Professor Jonathan Van-Tam says frontline workers, including those in the NHS, will be the first to get a new antibody test for Covid-19.
Everyone aged five and over is made eligible to be tested for coronavirus if they are showing symptoms, which are expanded to include a loss of taste or smell.
The prime minister says a Test and Trace system will be up and running by June 1 but the roll-out of the smart phone app will come later.
He says 25,000 staff would be in place by the start of June and they would be capable of tracking the contacts of up to 10,000 new Covid-19 cases a day.
Mr Hancock announces that tests are available to anybody in the UK experiencing symptoms, including children under five.
The NHS Test and Trace officially launches across England. The service recruited 25,000 contact tracers to identify people who have been in close contact with someone who has tested positive for Covid-19 and advise them to self-isolate.
However, the accompanying app is delayed by several more weeks as the Department for Heath admitted “some staff initially encountered issues logging on to their systems”.
The target to build testing capacity to 200,000 tests per day in the UK has been reached a day early, according to Mr Hancock, with a total of 205,634 tests available.
One third of people who tested positive for Covid-19 could not be reached by the NHS Test and Trace programme in its first week of operation or failed to provide details of their contacts, according to data.
Apple and Google take over the design of the Track and Trace app from the NHS’s digital arm NHSX as the government abandons its own app.
But Matt Hancock could not say when the app would be rolled-out.
Mr Hancock said: “We’re working on it. We’re not going to put a date on it I’m afraid because I’m absolutely determined that, whilst this technology can help, it’s got to be working effectively.
“But I am confident we will get there – we will put that cherry on Dido’s cake.”
The leader of the opposition Sir Keir Starmer challenges the prime minister about Test and Trace in light of figures showing only a third of people contacted by the programme in the first week of operation.
"If two thirds of those with Covid-19 are not being reached and asked to provide contact details, there’s a big problem isn’t there?" he asked.
However, Mr Johnson defended the scheme calling it an "effective cluster-busting operation".
New figures reveal the Test and Trace system failed to reach thousands of people infected with coronavirus since it began.
While a majority of those who test positive are reached (more than 70%), tracers failed to get hold of a huge 24% of people since May 28.
Fewer than one in 10 people (7%) got a result within 24 hours of taking a home test, while 15% got a result within 24 to 48 hours.
The government admitted that England’s Test and Trace programme broke a data protection law.
The Department of Health and Social Care (DHSC) acknowledged it had failed to carry out a risk assessment on how the system would affect privacy.
Local health protection teams continue to be more successful than call centre workers at reaching close contacts of people who have tested positive for coronavirus.
However, the PM maintains the system is "world-beating".
He said: “If you look at what we are doing, actually I think it certainly is – it certainly does fit that description of ‘world beating’.
“I think I’m right in saying that we are now testing more – per head of population – than virtually any other country in Europe, certainly, in America they are testing a huge number of people.”
Labour said there were “growing concerns” about outsourcing giant Serco’s role in the Test and Trace programme amid reports call centre contact tracers were being “paid to watch Netflix”.
The party also said the service was nowhere near “world-beating” and was unable to tackle local outbreaks.
The government has announced it was strengthening regional test-and-trace powers in England while axing 6,000 national contract tracers.
Health minister Edward Argar said the move will create a “hybrid system” with national callers alongside a local door-to-door approach.
He said: “We’re reducing the number of contact tracers nationally through that Serco contract from 18,000 to 12,000 and throughout we have worked closely with local public health officials, but we are strengthening further that relationship so you will still have that national calling, that national push, to make contact.
“But for those hard to reach or for those people who can’t be contacted then you’ve got this door-to-door approach as well.”
The health secretary defends the decision to promote Baroness Dido Harding to interim leader of new health agency, the National Institute for Health Protection, which is replacing Public Health England.
The Tory peer's promotion causes widespread anger among health experts and MPs who have questioned her credentials.
The Health Secretary said ministers were "working as fast as we can" to achieve population-wide mass testing so restrictions can be eased.
The Test and Trace system fails to reach its 80% target for the ninth week in a row.
Director of testing Sarah-Jane Marsh issues an apology to people unable to get tests, saying there is capacity at testing sites but laboratories processing the tests are at a “critical pinch-point”.
The prime minister outlines the "Operation Moonshot" approach of mass testing from home.
The government considered shelling out up to £100 billion for a mass at-home coronavirus testing programme, but experts were cautious about its ability to deliver as a reliable at-home test has yet to be developed.
Meanwhile, ITV News speaks exclusively to a call handler for NHS 119 - the NHS call centre that books test appointments - who describes the system as "absolutely shambolic".
The call handler, who spoke on the condition of anonymity, said people were being left on hold for hours only to be told that there were no available appointments.
She said: "The site is just not allowing anyone to complete and get an appointment. It's not good and they should be ashamed of themselves."
She added: "We're talking to customers who are sat outside testing stations, with nobody going in them, and we're telling them it's volume, so we can't get them a date or a time, and they know that's not true. "They know this website isn't working, it's unfit for purpose. Let people get into these test centres, people are actually trying to do the right thing but they can't, their hands are tied. They go to a test centre and if they haven't got this code, which they cannot get hold of, they can't go in."
The percentage of close contacts reached through Test and Trace is the lowest since its launch.
The government announces the NHS Covid-19 app is due to launch across England and Wales on September 24.
The health secretary said it could take "weeks" to resolve issues with testing after he admits "operational challenges" related to a surge in demand.
There are widespread complaints that the UK's testing regime is inadequate, with some people being forced to drive for hours to get a test, and others having to wait days for appointments or returned results.
Baroness Harding denies that the test and trace system is failing but acknowledges that a surge in demand was significantly outstripping capacity.
The NHS Covid-19 app is launched across England and Wales to support the NHS Test and Trace effort, following months of delays, technical hitches and privacy issues.
More than one million people download it in England and Wales on the first day of its release.
Government figures show just one in 10 coronavirus tests are being processed within 24 hours in England.
Nearly 16,000 cases went unreported due to a technical error with an Excel spreadsheet, causing cases to soar in dozens of areas of England.
The health secretary said that up to 48,000 people could have unwittingly spread coronavirus on to others due to the error.
Figures reveal the lowest Test and Trace contact rate since the scheme began.
Meanwhile, as few as one in four people testing positive for Covid-19 receive their results in 24 hours.
The Test and Trace system reached just 68.6% of close contacts of people who tested positive for Covid-19 in England in the week ending September 30, the lowest since the scheme began.
The figures are starkly different to those cases handled by local health protection teams where 97.1% of contacts were reached and asked to self-isolate in the week to September 30.
The Test and Trace app is updated after users reported confusion from a notification suggesting they may have been exposed to the virus.
Test and Trace records its worst ever week with data showing just 62.6% of close contacts of people who have contracted coronavirus in England were reached through the system in the week ending October 7.
More figures show Test and Trace has hit a new low with just 59.6% of close contacts of people who tested positive for Covid-19 in England reached through the system in the week ending October 14.
The PM said: "I share people’s frustrations and I understand totally why we do need to see faster turnaround times and we need to improve it.
“We need to make sure that people who do get a positive test self-isolate – that’s absolutely crucial if this thing is going to work in the way that it can.”