Primetime TV programmes such as The Great British Bake Off and Game of Thrones have helped fuel a boom in “dual-screening” by consumers – watching television while simultaneously browsing and shopping online – new research has revealed.

Reinforcing the ongoing “Bake Off effect” on retail sales, shoppers are snapping up specialist bakeware such as tins and cookie cutters from the comfort of their sofas via their laptop, tablet or smartphone during the programme, according to online marketplace eBay.

The data is published as part of eBay’s first UK retail report, published to coincide with its 21st anniversary. The report provides a snapshot of the way the UK bids, buys and sells, with a focus on the rise of the dual-screening phenomenon. The findings are based on all eBay UK’s sales and search data over the last year, based on the habits of the over 19 million Britons who visit eBay every month.

According to Ofcom, two-thirds of people own a smartphone, using it for nearly two hours every day to browse the internet, access social media, bank and shop online.

Using minute-by-minute data information and by breaking down user activity by device, eBay has tracked shopper behaviour at precise TV moments – including live broadcasts and in the weeks following box set releases.

During the season 7 premiere of The Great British Bake Off in August, eBay saw a 67% rise in consumer interest in baking products while the show was on air, soaring to 133% during the hour immediately afterwards.

The programme, now one of the most popular in the UK – although switching from the BBC to Channel 4 for the next series – has sparked a boom in the art of home baking and a nationwide consumer fascination with soggy bottoms and fancy biscuits. Such is the power of the Bake Off effect over sales that the UK’s supermarkets and retailers spared no expense in making sure they were fully geared up to meet demand as the new series kicked off.

Of other TV blockbusters, eBay UK recorded a sixfold increase in searches for Game of Thrones merchandise – box sets, books and branded T-shirts, mugs and even jewellery – on the day after the season 6 finale aired, with 71% of these via mobile.

Following Team GB’s 11 cycling track medals at the Rio Olympics, exercise bikes and Brompton bicycles were two of the fastest-rising search trends on the site, with Bromptons viewed more than 110,000 times during the remainder of August.

Even merchants selling tweed flat caps have enjoyed a fillip thanks to the success of the drama Peaky Blinders. Following the season 3 premiere on 5 May 2016, sales of flat caps (as worn by Cillian Murphy’s character, the Birmingham gangster Thomas Shelby) tripled in volume, with demand remaining strong throughout the series.

“Primetime television breaks have long been the gold standard in advertising, with millions spent on ads that air during some of the nation’s favourite programmes,” said Murray Lambell, the director of UK trading at eBay. “Our trends report demonstrates the power that popular shows have in and of themselves – as evidenced by the sudden burst of flat cap sales we experienced during Peaky Blinders, or the baking interest seen throughout GBBO.”

The retailer said that each series of GBBO had sparked an average of 45% sales increase for one of its sellers, Yolli Kitchenware. Yolli director, Richard Loynds, said: ‘We first decided to start selling baking products when we noticed more and more people were buying our lollipop sticks to make ‘cake pops’ – a cupcake you eat off a stick. Whereas we previously sold exclusively to other businesses, we are now able to sell to individual consumers – tapping into the trend of baking, with cupcake cases being hugely popular.”

Established in 1995, eBay is one of the largest marketplaces in the world today, with 164 million active buyers and 1bn listings worldwide. A total of 57% of eBay’s sales are generated by mobile phones.