Item location could be provided by a phone app today. My feeling is that they don't do it because they don't want you to know the exact location because they want you to browse the aisles in hopes that you'll throw something into your cart that you weren't planning to. Same reason that supermarkets put milk and eggs at the farthest corner away from the door.
The Home Depot app is how I find everything when I go there. I think the other stores didn't do it yet because the isles and bays in most stores don't have visible numbers. And without that they need to wait a few years for deployed internal location technology to improve a bit.
