Some new Huawei phones and some older mobiles cannot run the NHS contact tracing app being trialled on the Isle of Wight, NHSX has said.

Dr Geraint Lewis, who is in charge of the development of the NHS Covid-19 app, said that the new tool will only work with newer operating systems on Apple and Samsung phones.

Speaking to BBC Radio Solent, he said phones needed to have the capability of running Bluetooth Low Energy (BLE) and to be running either Apple ios 11 upwards or Android 8 upwards.

Several listeners had contacted the radio station to say that the app, which is being piloted on the island before being rolled out nationwide, was not working on older devices.

Dr Lewis said: “There are three reasons why the app might not work on a particular smart phone, it’s either the development team has not got around to supporting that particular phone.

“For example Huawei phones we haven’t quite got there yet but we are hoping to do that very soon.

“The second reason is if the phone itself doesn’t have this thing called Bluetooth Low Energy in it, certain older phones don’t have BLE and that’s the piece of technology we use to measure distance between phones.

“The third reason is the operating system, we currently support ios version 11 and upwards and Android version 8 and upwards, so if you can update the operating system that should hopefully help.”

A spokeswoman from Huawei said it was working to ensure the app would work on all of its devices, adding that the majority of Huawei smartphones have access to the Google Play store from where the app can be downloaded.

Meanwhile, another listener complained that the app drained the battery on their phone but Dr Lewis said that it had been designed to be low energy and only used 1% of battery on his phone and asked for people with problems to give their feedback to NHSX.

It is not a tracking app, it doesn’t know geographically where you are, all it is measuring is the distance between your phone and somebody else’s

Dr Lewis explained that Android phones request permission to use location services because the system bundles it together with bluetooth permissions and he had written to Google to point out that this was “confusing”.

He added: “It is not a tracking app, it doesn’t know geographically where you are, all it is measuring is the distance between your phone and somebody else’s.”

Explaining how the app works, he said: “If you download the app, it starts taking anonymous measurements of how far away you are from other app users and it stores that information anonymously on your phone.

“If later on you develop symptoms of coronavirus, either fever or continuous new cough, then you can choose to send that information to the NHS, then we will notify anonymously those people you have been in close contact with and then arrange for a virology swab test delivered to your door in a few hours.

“The system is there to protect the whole community, so if sufficient numbers of people download and use the app everyone will be protected regardless of whether they themselves have a phone that is compatible.”

He added: “The huge advantage of an app over more traditional forms of contact tracing, is that you can almost industrialise the process, it’s able to send notifications very rapidly to people very soon after they have developed these symptoms which is the time when they are at their most infectious.”

Dr Lewis said that 55,000 people had downloaded the app so far but it was not possible to say that all of those were on the Isle of Wight.

A spokeswoman from Huawei said: “We are working with relevant partners to make sure the app works on all Huawei devices. Huawei smartphones have been on sale in the UK for nearly a decade.

“During that time we have sold millions of devices and have become a market leader across Europe. All Huawei smartphone devices in the UK are based on the Android operating system. The majority have access to the Google Play store, where the NHS Covid 19 app can be downloaded.”

A spokesman for NHSX said: “The majority of those with a Huawei phone will be able to download and use the app given most devices are running Android and can use Google Play store.

“For the small number of Huawei devices that use the AppGallery, NHSX is working hard to provide support.”