A new app which allows patients to book appointments, order prescriptions and view their medical records has been launched by NHS England, although the vast majority of people won’t be able to use it until the summer.

Despite a pledge that it would end the 8am scarmble for appointments, a large majority of GP surgeries have yet to sign up for it.

As a result, it has been criticised by users on the Google Play store, with one describing it as “almost, but not entirely, functionless”.

Although it launched the app on New Year’s Eve after piloting it in 30 practices, NHS England said they do not expect significant numbers to begin registering until winter pressures abate around April.

It added that it had not publicised the app as it was trying to avoid burdening surgeries with the roll out, although it expects them all to be signed up by 1 July.

Those trying to use the app were less than impressed however.

“This app is almost, but not entirely, functionless for me as although I use GP online services I can only use it as a symptoms checker,” user Georgie Orman wrote on the Google Play store.

Another, Joe McDonald said there was “no functionality”. He added that the app concept looked good, but he questioned whether it should have been launched in its bare bones state.

He said it was “currently a long way short of a minimal, viable product.”

Patients whose practices are early adopters said the app was already proving useful, barring some teething problems registering, which requires a code from the surgery or an NHS number and video to confirm identity.

However downloading the app will still give access to the NHS-verified symptom checker.

Over time the app is expected to be a “one-stop shop” for NHS features, to help banish telephone queues for appointments and act as the launch pad for ambitions in the NHS 10-year plan – such as the pledge that every patient will be able to access to video GP appointments by 2024.

However the app is not available to patients in Scotland, Wales and Northern Ireland as health responsibilities are devolved.

Health secretary Matt Hancock said: “The NHS App will give patients more control over their own healthcare and revolutionise the way we access services. It marks a shift towards a truly digitised NHS and will allow patients to secure a GP appointment with the click of a button, rather than having to join a queue of callers.”