Last week at SES New York, I had the chance to catch up with Alex Muller, CEO of new mobile shopping search product Slifter.

The mobile application allows users to search for products that can be found in local stores, including how many are on the shelf. To do this, it works with big-box retailers such as Best Buy to pull in their retail feeds and make them searchable in a mobile application interface.

This takes the opportunity being tapped by Krillion, NearbyNow and a few others and brings it to the mobile device in a different way (NearbyNow has SMS-based product search). The opportunity, in a nutshell, is to build products that take the reality to heart that the majority of U.S. retail activity happens offline in physical stores (as opposed to e-commerce). Effectively leading these offline conversions and tracking them with things such as coupons, or reserve online, is the goal.

Slifter brings an added dimension to the opportunity given that the phone is present when the consumer walks in the store, allowing the potential for more effective tracking (think mobile coupons or saving search results on the phone).

Having local product search take place on the phone also extends the use case beyond searching at home to include more serendipitous or on-the-fly product searches while out on the town. This makes a lot of sense in certain use cases, such as holiday shopping, where finding a hot item in stock, while scrambling around town to find it, can be a valuable proposition.

Muller explained how the flat screen television in Slifter’s booth at SES was found at a Circuit City in Manhattan using the product. The price it was able to find was cheaper than what was actually on the floor because of a brand-new promotion, which Slifter picked up before the floor sales associate knew about it.

“We brought the phone in and showed them and they didn’t believe it until they checked their system to see with surprise that the item had just been marked down,” said Muller. “Someone at Circuit City corporate had decided they wanted to move this product and we knew about it before the floor sales rep did.”

This opportunity will grow as mobile search adoption itself does — a result of improving standards and more mainstream penetration. As we pointed out last week, mobile and local are inherently related and many of the adoption increases and product developments expected in mobile will involve local search.