No, IOTA is not blockchain technology, it is it's own thing.
There are similar projects like byteball and nano, but they are all slightly different in their tech.
It is often called blockchain 3.0 because it is in the crypto world, but technically that isn't correct.
It is not an evolution of the blockchain but an "original" piece of tech.

But here's the thing, it is still buggy as hell.
The reason why is that in order for the IOTA tangle to operate properly it needs a large amount of users and volume.
It doesn't have that now so it is actually being centrally controlled with plans to "take off the training wheels" in the future.
Also, simply storing your iota has proven to be a monumental challenge.
You often have to attach, reattach, rinse and repeat just to see your own iota.

It has a lot of good going for it, but I'm thinking that unless IOTA shows some major steps towards development and implementation that it will be overtaken by other projects.
Just look at nano, it is already scalable, fee less, and decentralized and it already works great.