What does 'cool toy' mean?

Cool toy is not a technical term. Here, cool is an informal way of saying excellent or fashionable; see the definition number 7 at Merriam-Webster or Wiktionary. What is cool is highly subjective; different people will have different opinions. For example, some might say that iPhone is cool; others might disagree. A cool toy doesn't have to be electronic. For example, I think that LEGO is extremely cool. (But again, others might disagree and say that Playmobil is cooler.)

In this context, toy is defined New Oxford American Dictionary as follows:

an object, esp. a gadget or machine, regarded as providing amusement for an adult

So, yes, an iPad, or similar fancy electronic gadget, could be considered a "cool toy". Other examples of toys are luxury cars or motorcycles.

Cool here is used informally to mean fashionable. When the article says it is more than a cool toy, it means the toy is not just fashionable but has real value.

cool toy means a gadget that you just MUST have because it is is the latest 'thing', but you really don't need it.

In this context where it says more than just a cool toy, it means that it has a practical purpose that you can use for more meaningful tasks (not just to play with...).

A few month ago I said 'awesome gadget' than I walked around considering whether or not I should buy an iPad. It's a cool toy nobody really needs it, but my wife.