When I saw that it had won the 2017 Spiel des Jahres I took a look at Kingdomino. On discovering that it was only £15, and that games could be played in about 15 minutes I decided to pick up a copy.
So far I've played games with both swampers
and both of them picked it up quickly and enjoyed playing it.
It's based (surprisingly enough) on the idea behind dominoes - or, at least, the part of dominoes where you have tiles with two ends and need to match them against each other. In this case the different ends are different terrains (grass, mountain, etc), and you score by forming areas of the same terrain*. Each turn you have to make a judgement between going for the tiles that score the highest, versus going for lower-scoring tiles which allow you make the first move the next turn.
I enjoyed it, and I'm definitely taking it on holiday. If you're looking for a filler game then it'll do a great job of that.
*It's a bit more complex than that, but not a lot.