• by Chuck Martin , Staff Writer, May 13, 2015

Any retailer not taking mobile shopping seriously is making a serious mistake.

I’m not talking about the activity of shopping from a phone but rather the influence the device is having on what people ultimately purchase in a store.

While most consumers don’t yet buy things from their smartphones, the impact those devices is having on physical retail sales is significant.

A couple of years ago, Deloitte Digital started surveying thousands of consumers to measure the actual influence of mobile on in-store shopping.

This has always been one of my favorite pieces of mobile research, especially after my last book was titled Mobile Influence.  The first of these Deloitte studies in 2012 was named The Dawn of Mobile Influence.

That’s where Deloitte identified that while many merchants were concerned with showrooming, viewing a product in a physical store and then buying online, an in-store shopper using a mobile device was actually more likely to make an in-store purchase.

The next study, The New Digital Divide, identified what Deloitte called digital influence factors (in my book, I had called them influence points), which directly impacted more than a third (36%) of total in-store retail sales.

The mobile influence on retail sales at that point was 19% of all sales.

The latest study, out today, pegs mobile influence at 28%, translating to $1 trillion of sales.

Most shopping studies we see focus on the growth and trends in mobile and online activity. Many of those studies are great measurements of how mobile is being used to buy online or to research products before purchase.

The Deloitte study focuses on the 94% of sales still taking place in physical stores and the role that mobile and digital play on that number.

For context, 7% of retail sales last year, about $305 billion, were online with the remaining more than $4 trillion occurring through traditional physical stores, according to Deloitte.

The latest study comprised an online survey of 3,000 random consumers, weighted to be representative of the U.S. population. An additional subset of consumers was used to provide information about how they use digital devices to shop for specific product categories.

Deloitte also measured the impact of mobile influence by category, with electronics and home furnishing having the highest and food/beverage at the bottom. Here’s the mobile influence by category:

• 37% -- Electronics
• 35% -- Home furnishings
• 30% -- Apparel
• 29% -- Automotive
• 29% -- Entertainment
• 29% -- Baby/toddler
• 23% -- Health/wellness
• 20% -- Misc. supplies
• 17% -- Food/beverage

While most shoppers aren’t yet using their smartphones to make a purchase, a large amount of  mobile influence on retail is happening under the radar.