Fashionistas, particularly millennials, like to personalize what they wear. New backpacks from a startup called Pop-I will let wearers display personal photos right on a built-in digital screen. Pop-I's president, Vikram Joshi, says that "with a push of a button, you can completely change the look of your backpack to try to match your style or your emotions or feelings." It can be a photo you just snapped, or something from your photo gallery. The backpacks are among the products on display at this year's CES gadget show in Las Vegas. They will come out later this year and range in price from $99 to $399, depending on the size of the screen and the material of the backpack. Leather versions are more expensive than canvas. Pop-I is looking to expand to other products, like clothing.