It indicates that 71% of 55-to-75 year olds now own an app-capable handset.

The research also suggests that the age group has seen a faster adoption rate than any other over the past five years.

But it also highlighted that members of the demographic tended to use their smartphones less than younger people.

For instance, about 20% said they checked their phones within 15 minutes of waking compared with a national average of 56%.

And about 50% had Facebook installed compared to a 70% figure for all adults.

The study was based on a sample of 1,163 people questioned between May and June this year.

Deloitte suggested that the 55-to-75-year-old group's higher than average wealth might make members more likely to buy premium handsets, although some will have inevitably started using a smartphone as a consequence of being given a hand-me-down from their children.

Its research team also acknowledged that some first-time buyers might have felt forced into making the purchase.

"A growing number of parking meters may encourage payment via mobile phone, for example with a smartphone app offering the greatest convenience," they said in a company report.

"It may [also] become increasingly difficult to order a taxi in cities without using an app."

One industry-watcher highlighted that some of the older population should have benefited from some of the changes made to smartphones over recent years.

"Modern smartphones have much bigger screens, so as older people's eyesight deteriorates they are easier to view, and they have louder speakers too" commented Ian Fogg from the IHS Technology consultancy.

"The software has also become easier to use over the years - quite a few of the mainstream Android manufacturers now offer streamlined versions of their app launchers aimed at elderly people, and Apple has a lot of built-in accessibility features in iOS too."

Another expert added that a feature added to Apple and Samsung's latest handsets might attract further members of the older generations.

"Facial recognition is a very popular authentication mechanism among the elderly," said Dave Birch from Consult Hyperion.

"Research suggests older people like the idea of being able to just pick up a phone and look at it, rather than having to fiddle about with buttons to press or having to put on their glasses to type in a password.

"There's a lot of stories about people using photos to fool the tech, but actually the quality of the systems has come along in leaps and bounds."