A select group of people are going to find Pocket Trains impossible to put down. It's a perfection of NimbleBit's simple, free-to-play formula, wrapped in the trappings of a trainspotter's fever dream.

Then there's the twee graphics, the cheeky winks, and the sweet sense of humour that permeates every chuff and chug. The whole game is polished and poised, designed to make you tap and spend freely.

And to a degree, it works. There's the same compulsion here that runs through Pocket Planes, and watching your rail-empire extend like a multi-coloured spider across the globe is enough to warrant a smile. But, at its core, Pocket Trains is just more of the same.

Train to game

You start out with three trains and a handful of stations in Europe. Each train can carry a set number of cars, and is confined to a single coloured track. If you want more than one train using the same stretch of track, it'll cost you.

It'll cost you to spread out across the globe as well. First you need to build a stretch of railway, then you need to pay to add it to your network. If you're starting a whole new line, you'll need to build a new train as well.

Cheaper trains are pretty easy to come by and only require three different parts to make. Throw in another three parts and they get a larger fuel store. Faster, better trains need more parts, and finding the requisite chunks of engine is a much tougher exercise.

Your trains refuel slowly over time if you leave them standing in a station, or you can spend a few Bux - one of the two currencies in the game - in order to top up their tanks straight away. You earn coins, the other currency, by delivering various goods and people from one station to another.

Tracking stats

There are a variety of spanners waiting to be thrown in the works, though. Sometimes your trains break down, and you'll need to pay coins or parts to fix them. Other times you'll find a station doesn't have anything your train can deliver.

Do you join together some existing lines and head back to a different station, or branch out and build a new and expensive section of track?

You can deposit up to five carriages in each station to collect later, which is especially useful if something that's going to earn you a lot of money pops up on a line you can't deliver from.

When the trains are in transit there's not much for you to do but sit back and wait for them to arrive. You can boost their speed with Bux to get them where they're going quicker, or keep an eye on the screen and grab any coins that float by.

Pocket Trains is a game of waiting, then. You let your trains potter around the map, collecting the cash from their deliveries and then loading them up for the next run. It's simple, it's entertaining, and we've seen it all before.

Will you choo-choo-choose it?

NimbleBit is the best at what it does, and Pocket Trains is another impressively simple time-waster. There's nothing to it, really, and when you peel away the cutesy presentation and chiming music you're left with a clock and some coins.

There's nothing wrong with that, particularly, and the exterior of the game is sweet enough that it's difficult not to get a little swept up in your rail-based adventure to begin with.

But after a while, when things become more grind than glee, and you're trying to juggle multiple trains with multiple problems all across the globe, you can't help but think the game is getting to be a little too much like a job.

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