There are many styles of Thai snack. I have been eating both new and old style snacks for this month. My favorites are and will always be the old style. As Thailand develops and convenience foods make inroads, the old style snacks get pushed out. In Bangkok, or at least in my neighborhood, these roving vendors with their baskets are less common than they were just a few years ago.
This vendor sells coconut jellies and fruit jellies.
The jellies are kind of like a finger jello. Quite firm really.