Having a crack on Harbor Master means spending much of your time spinning around in circles.
As you wait for each dock to open up, the only way to survive is to send any ships waiting in the harbour on round trips – quite literally.
Managing their solo circles has much in common with taking charge of a line of spinning plates.
Of course, Harbor Master is a return journey in itself. Windows Phone 7, now playing host to the likes of Fruit Ninja and Flight Control, and with Angry Birds waiting in the wings, is in a cycle of repetition - calling on iPhone's roll of honour one by one, reliving the platform's highs on a two year delay.
When the end result is games such as Harbor Master, however, it seems churlish to complain.
Water worksAs was the case almost two years ago, Imangi Studios's line-drawing game owes much to Firemint's Flight Control, though its obvious similarities don't result in any drop in the quality of gameplay.
With seven levels on offer, the task is to survive in each one for as long as you can, redirecting the many ships that stream into the harbour towards the docks if and when they are free.
Once each craft has dropped off its cargo, you then have to guide it back out again, avoiding the flurry of ships looking to take its place.
The simple act of doing so is certainly straightforward in practice: drawing a line from each craft to its intended destination is all that's required.
Keeping the game going means ensuring none of the ships collide, however. It's a challenge that's further complicated by the differing speeds of the three different types of boats.
Spinning aroundThe smaller ships, for instance, motor at some pace, and they spend far less time dropping off their load in the harbour.
This, in turn, means the docks themselves are freed up more willingly – a crucial factor if you're looking to avoid the water becoming overrun with boats.
Not that the ships themselves are the only hazards at hand. Harbor Master itself throws in a few hurdles of its own to keep you on your toes – perhaps, most notably, the twisters that skirt over the water in Cyclone Island. Contact with them isn't fatal, but it changes the direction of any ships that hit it.
Cannon Beach offers an altogether more explosive setup, with cannons on hand to shoot down any pirates looking to steal your cargo.
Dock idolBut Windows Phone 7's ship pulls into Harbor Master's bay with its own load somewhat light.
As with all releases on the platform to date, the multiplayer those on iPhone will be accustomed to is missing from its set up here.
This is as a result of imposed limitations, of course, rather than a lack of desire from the developer.
Still, even the absence of any online elements can't muddy Harbor Master's waters all too much.
Though already sailing a familiar course, there's charm enough in Harbor Master to make it worth a second voyage.