Fascinating things can happen when you impose fresh rules and limitations on a familiar game.
That's certainly the case with Crossgrams, where the humble crossword meets the word jumble, and where a simple block-shuffling control system brings everything into sharp focus.
It's the way in which you shift those letters that's the thing here. You can grab and slide any letter along the width of the game grid, but not vertically.
I'm aware that this sounds like a rather dull twist on the formula. But it transforms Crossgrams into an intuitive yet compelling puzzler.
It makes solving top-to-bottom words a completely different (and more challenging) process to the left-to-right words.
We've mentioned the drag and slide control system, but you can also pin letters in place when you think you've got a word nailed. I would have appreciated a second pin colour to help you separate words you think you've got from those you're certain about, but that's a minor quibble.
The presentation is sharp and sober, with a pleasantly ambient, twinkly piano score helping you to relax into that half-dreamy, half-concentrating state that's so helpful when thinking up words.
You can pay for new colour themes if you like, but you're better served splashing out on one of the two additional Puzzle Packs at 99p/99c a pop, or one of the two tougher Challenge Packs for £1.99/$1.99 each.
You get a free Starter Pack and a free Challenge Pack from the off, and there's also a free Daily Puzzle. Which is just what it sounds like, and will likely be enough for a lot of players.
This is the kind of puzzler you'll happily dip into for 10 minutes or less a day. Below its simplicity and familiarity, though, lies a clever twist on the word game that will absorb you way more than you might expect.