Whether you're writing them, waiting in them, or dancing like a constipated marionette in them, nothing good has ever come of lines. You can add drawing them to that list now, thanks to Puzzle Restorer, a logic game that turns lines into a brain-melting weapon to be feared.

In principle, Puzzle Restorer offers up a relatively simple little premise: draw a single, continuous line from one coloured block to another, filling in the blanks to complete a picture.

For the first few stages it's a relatively straightforward - even soothing - affair, as you glide effortlessly across the screen, taking in the relaxing jazz accompaniment.

Testing times

Slowly, though, Puzzle Restorer starts introducing new rules and the game's quaint little concept soon flexes its muscles, turning into a devious, brain-frying git of a thing.

Drawing a path through a black square, for instance, has no effect on the grid, meaning it's a handy strategy for reaching areas on the other side of sections that need to remain blank.

That's all well and good, but colour-mixing soon rears its head, and suddenly you're in charge of drawing two or more separate continuous lines, overlaying different colours to create whole new ones.

Count yourself lucky

That in itself starts to test the boundaries of your intellect - not to mention your patience - but there's another issue to contend with too. You see, each puzzle has a total tile limit, meaning your squiggles can only pass through a set number of squares before you run out of paint.

Suddenly, you need to take into account the fact that primary colours can happily pass through secondary colours without influencing the board - and use this new knowledge to construct the shortest routes possible to meet those stringent requirements.

It's increasingly hair-tearing stuff, pure hot rage slowly bubbling up while that supposedly soothing jazz tinkles mockingly in your ears.

Of course, as is the way with these things, that means victory brings with it a rush of vindication, making for a genuinely satisfying puzzle experience.

Coming undone

Puzzler Restorer handles everything with responsive, intuitive touch controls, meaning you've nothing to worry about beyond mental acrobatics.

There's a minor niggle insofar as the continuous line concept means you're sometimes, frustratingly, forced to undo whole swathes of work if you make a mess, but that's more a by-product of the game's core design than a flaw.

With its pleasing, minimalist presentation, 64 increasingly taxing puzzles, and even a handful of secret stages - each introducing a whole new set of mind-boggling rules - there's a whole lot to like about Puzzle Restorer.

It's super-accessible in its setup, yet fiendish in its complexity, making for a brain-busting gem of a title that's as rewarding as it is infuriating.