The ludicrously overstocked shelves of the App Store are groaning under the weight of word games and simple strategy sims, so it takes something special to grab the attention of jaded app shoppers. I think Quarrel Deluxe should do it. Developed by Dundee-based Denki Games, creator of the seminal pre-iPhone puzzler, Denki Blocks, it is an elegantly designed combination of Scrabble and Risk, in which the player must gain control of all the squares on a series of environments by beating AI opponents at a word creation game.
Each side starts out with a small army of tribesmen and a set number of squares. Players then take it in turns to try to overtake the territories nearest their own, by starting 'quarrels' with the tribesmen of other players. These quarrels are essentially Scrabble word creation tests – you get a selection of letters, each assigned a score, and you have to create the best word possible. You're limited, however, by the number of tribesmen you have on your square; if you take four men into the fight, you can only create a word up to four letters long. If you manage to defeat a square that has a greater number of enemy tribesmen on it, you get to take one of theirs as a prisoner, and he fights with your men.
When you gain a new square, you move several of your people on to it, but you need to divide your armies so that you don't leave any areas of your territory poorly defended. The skill of the game is knowing how far to push your territory in a single turn – try to take too much land in one go and you end up with several squares defended by just one lonely solder – they're asking to be attacked. At the end of each turn, the game sends in a set number of reinforcements to each team, and you can also gain extra men by filing a gauge that counts up your word scores. Meanwhile, when AI players are challenging each other, the player gets to take part in a bonus challenge which involves making the best word possible with the letters that your opponents are fighting with; the better your word, the most points are added to your gauge.
It has to be said, this is not a light puzzler in the Popcap ilk. The rules take a little time and effort to appreciate, and the richness of the territorial strategy only becomes evident after several games. Luckily, there's a really nice tutorial mode that guides you through the basics. Once you've got to grips with everything, you have a beautifully presented, enormously deep strategy word game, that's lovingly filled with compelling subsidiary features (like dictionary definitions of all the words you create). You fight on a variety of landscapes, each with strategic quirks, and all the AI opponents have different styles, some brilliant at word play but lousy at territorial strategy, others masters of both.
The downside is the lack of a multiplayer component. The game was designed (and originally demoed) as an Xbox Live title and playing it against friends on the sofa will surely be the optimum experience. Multiplayer is certain to be added to the smartphone version of the title in future iterations, and I'm hopeful an XBLA version will still arrive at some point.
As it stands now, and for £2.99 (though there is a limited free edition to try too), Quarrel Deluxe is a must buy for Scrabble and Words With Friends fanatics who want to try a whole different type of lexicological challenge. There is great satisfaction to be had in turning the course of a war with one or two tactically brilliant land grabs and a few clever words; I've been down to my last land tile and somehow fought back to victory. And when you have enough tribesmen on a tile, there's a chance to multiply your score by solving the eight-letter anagram that accompanies every quarrel, so you even get to feel like a Countdown contestant.
Quarrel is just a lovely, skilfully-crafted joy. Denki's genius is in making you feel that hours in the game's company have been educational rather than a time-killing indulgence. That is the loftiest aim of all word games. Few really achieve it.
• Quarrel Deluxe was reviewed on iPhone 4
