If they're drying out faster than you have time to water, that's a problem, but generally fast drying is a good thing for a container soil. My approach would be to water more often, find larger pots, or use a mix that dries less quickly as a last resort.

Haven't heard of that product, but it's probably like the moisture crystals which are a complete fallacy. They do not release moisture quickly enough to be useful, and the expansion and contraction at the root zone can't be good for plants.

I have used the product that you mix into the soil and it fills up with and holds water. (Starts out like crystals, but after watering, it looks like clear jello in the soil)
It works. But, since potting soils started coming out with the option of "Moisture Control", I don't use it anymore. It is less expensive and less trouble to get it all in one product.
Sometimes pots dry out too quickly because there are too many plants in them for the size of the pot. If you are needing to water more than once a day, even in the hottest of the summer, I'd say use a bigger pot or fewer plants (or both). This, of course, assumes you are using a good quality potting mix to start with.