Ok, so the trick for adding texture to cold milk and sweetening it with some agitation is a martini shaker. Add espresso, cold milk, a couple ice cubes and shake vigorously. Fill your glass with desired amount of ice, liquid should be cold after shaking, and pour over top ice cubes. Shaking the milk with the espresso creates a nice foam on top of the latte. It also sweetens it a bit. This may be a result of the milk we are using as well. I honestly haven't tried it with other milks so can't offer any comparisons. So with that being said, shake it up. Also, if you are adding other ingredients to your lattes give it a try in the shaker. You'll see a major improvement all around. The results as opposed to stirring in ingredients are leaps and bounds better. Let me know how it works for ya.
When we produce our Iced Lattes, we do not steam the milk to foam it, we use cold-foamed milk. This gives the same visual sensation as normal steam foamed milk, however the entire drink is nice and cold for the customer which they seem to prefer as this is one of our best selling drinks.
We utilize a wand type milk frother to create our cold foamed milk to top the drink with. These frothers do a much better job with 2% or fat free milk , but can be used on whole milk as well.