In both games, players take tiles from a central space and add the tiles to their personal princedom or kingdom board (depending on the game). For me, it's a toss-up between one of the best board games around in all categories, The Castles of Burgundy, and a solid game with killer two-player tile-laying action, Kingdomino. Many people have played Carcassonne, one of the most popular entries of the genre, but it's actually not the best example of the game - and certainly not the best for two players.
Tile-placement games are a mainstay for many board game enthusiasts, in part because of the fun of building a unique board each time you play.