Growing brand capability in and knowledge of digital marketing, as well as an increasingly technology-driven market, is putting digital agencies under increasing scrutiny, according to a new report. The Top 100 digital agencies 2015 report from Econsultancy found that the average fee income at the UK's biggest agencies increased by 25% last year. Despite the growth in fees, agencies report that clients are asking "more searching questions" than before and increasingly moving functions in-house.

Wimbledon has ramped up its digital strategy and is experimenting with a raft of new technology including Snapchat and iBeacons in a bid to engage with those unable to attend the 13-day tournament as well those fortunate enough to get tickets. However, amid the rise of live streaming social tools Wimbledon's digital boss Alexandra Willis has revealed that spectators will be strongly discouraged from using apps such as Periscope.

Sky News has learnt that Google is in talks with US buyout firm, Permira about making a combined offer for Dunnhumby, the sale of which Tesco hopes will help to rebuild its battered balance sheet. It was unclear on Thursday whether Google's interest was being handled through its main corporate entity or through another unit such as Google Capital, a growth equity fund backed by the US-based company. Either way, Google's association with the auction is likely to add renewed competitive tension to the process.

Mobile consumers believe that engaging with one minute of advertising on mobile devices is equivalent to GBP6.80 per consumer for advertisers, a new report has found. The international study of 4000 people, conducted by Opinium Research and commissioned by Millennial Media, found 79% of consumers understand that ads keep content and apps free, with only three percent paying for ads to not appear on their mobile devices. Almost three-quarters (72%) said they expected mobile ads to keep content free.

The Post Office has entered the mobile market with the launch of a pay-as-you-go service. The mobile offering -- called Post Office Mobile -- uses EE's network and is designed to offer an alternative for the 44% of mobile users who don't have a contract. Calls to both landlines and mobiles will be 8p per minute, while it will cost 10p per text -- which is up to 77% cheaper than other networks -- although customers will only be able to access 3G networks, not the faster 4G speeds.

National newspaper Web sites failed to capitalise on the general election to the same extent as BBC News online, according to the latest ABCs. The BBC's own figures show that the news site recorded 18.1m unique browsers on voting day, 7 May, and 28.3m the next day. It claimed that 19.3m of the unique users on 8 May went exclusively to its Election 2015 content. These figures are higher than any of the audited numbers provided by ABC for newspaper Web sites on those days.

LinkedIn has revealed the most influential brands in the UK, with Ernst and Young emerging on top while BP, "The Financial Times" and "The Economist" also appeared in the top 10. The report analysed the 18 million LinkedIn members across the UK and compiled a ranking by measuring a brand's unique engagement and dividing it by audience. The report found that the leading brands regularly share updates on their LinkedIn Company Page, while 73 percent make use of Sponsored Updates.

HMV has taken another step on its road to recovery with the relaunch of its ecommerce site two years after it went into administration. The online store will allow shoppers to buy physical CDs as well as DVDs with the same promotions on offer online as in its stores. Previously, customers were only able to buy digital downloads, with HMV putting the focus on content and entertainment. HMV hopes it can tap into a base of loyal customers who might want to buy from the chain but no longer live near a store.

Waitrose is hoping to restore customer trust in deals and promotions with the launch of an "industry-first" personalised offers scheme that offers customers 20% off the top 10 items they buy the most. The "Pick your own offers" scheme allows customers to select 10 items from a list of nearly 1,000 including fresh food, branded products and Waitrose's own brand. The 20% discount comes on top of any promotions -- such as two for one -- that might be running as well as Waitrose's price-matching scheme.

A new Nielsen study has found that up to 58% of UK grocery promotions -- across 200 retail categories -- are not making any money for FMCG brands as the supermarket price wars continue to put pressure on suppliers to discount products. And it isn't just UK FMCG brands struggling to make money from price-cut deals with the figure rising to 60% when monitoring the number of unprofitable promotions across each of the Western world's major markets -- the US, UK, Germany, France, Italy, Spain and Canada.