Another offering from Tetris creator Alexey Pajitnov, Marbly sadly comes nowhere near reaching the heights of his masterpiece. Not that we expected it could match that game - Tetris is pretty much perfect. Gone are the rectangles and reflexes, and in their place are balls of varying colour and the urgency of a sloth.

In ways, it's similar to Alexey's opus, but played on a top-down grid - it's as if Tetris and chess fornicated, spawning a genetically inferior offspring that looked a bit like the milkman, Bubble Bobble. In this game of chess, every piece is a brightly-coloured, marble-shaped 'queen'. They 'queens' can travel in any direction, as long as they aren't obstructed - as in chess - but can only move once.

The objective is to connect matching colours, forming a straight line, thus erasing them from the board. The minimum requirement is three of the same, with a maximum of eleven possible for the observant - with more efficient marble genocide awarded extra points.

You select one of the coloured balls by tapping it, also highlighting where it can travel. A second tap sends your chosen blob careening to the intended location. It's a game as much about planning ahead as it is about trial and error. If you make a wrong move you can use one of the various power-ups to undo your mistake, or even solve the puzzle completely. Yet, once these are gone, you can't even restart the puzzle without quitting out of it entirely. Of course, you could buy more power ups...

If you don't fancy paying, you can earn more of these by grinding through the puzzles, or completing one of the various challenges, but I found this frustrating. It wouldn't be so bad if the game had an addictive quality to it, but with the puzzles being varying sizes of the exact same thing, it gets old pretty fast.

The only interaction comes from sedate taps on the screen, whereas Tetris required a modicum of reflex-based skill. This, however, relies on the player having the patience to plan out all their moves before getting pokey. Without planning, you can easily leave less than three marbles of the same colour, or leave them isolated across the grid from one another, thus failing. Fine, but the game is never exciting enough to keep you interested long enough to make those decisions.

Another problem is the difficulty. Most of the puzzles are so easy that you literally can't fail them - with the balls refusing to move to an invalid position. Then, out of the blue, will come a puzzle that makes you want to eat your own face.

Once the aforementioned power-ups are gone, the only way to succeed these more difficult puzzles is to meticulously track every move you plan on making. It's just not very fun. On the more sedate puzzles you feel like you're a factory worker, going through the motions. And when the tougher ones pop up - with no preparation from the previous and no assists left - it feels like doing Pythagoras' Theorem at a nightclub whilst the doorman has you in a headlock.

The first volume of these puzzles is free, with a 100 coin fee to unlock each of the next two - or about £4.50. It won't be long until players run into this (pay)wall, and after that you have two options: pay to unlock, or a tedious grind. Even previously completed missions can be a burden when you're out of powerups, and these can only be purchased by grinding, or - again - paying.

An extra set of challenges are available for a chance to earn some coin, but it feels like a chore to do so, as tedium sets in quickly. If you fancy a bit of phone gaming on the morning commute, Marble is worth a punt - especially as it's initially free. Just be prepared, for once you've used your power-ups, the game's momentum will grind to a halt. Unless you're willing to cough up the dough. And the game's not worth it.

Played for 4 hours.