Early in World War II, the British were having problems ensuring they had sufficient supplies. Everything had to be shipped in, and the waters around the British Isles were teeming with enemy submarines.

Unable to understand the German military codes, the British had no way of knowing where the enemy was lurking. Germany had an impenetrable coding and decoding device, the small, typewriter-like Enigma machine.

In a stroke of luck, the British got hold of one from a crippled Nazi submarine, and they put a brilliant mathematician in charge of a team of cryptologists to uncover its secrets.

It was a formidable task, but, aided by a predecessor of the computer, Alan Turing and his team ultimately succeeded.

I've known the tale for some time and have thought a lot about the Enigma machine. To me, it has become a metaphor for any devices or apps that make life difficult, yet are necessary to master. Everyone has experienced that.

Maybe it was an automobile you had to learn to drive, a computerized sewing machine you had to learn to use.

The one that sours my life is the bike-sharing app for cellphones.

Don't get me wrong. The share bike is a tremendous innovation. I hold it in far greater esteem than I ever did other great milestones of human ingenuity that have emerged in my time.

The eight-track tape. The Walkman. And, yes, even the iPhone.

Great as they were－and a few still are－none can compare with the share bike, (though the iPhone could still come out ahead if they ever release a model that has a coffee-making feature).

The share bike has it all. It's fun. It's useful. It's healthy. It contributes to cleaning up the environment. Aside from the sticky, sweaty handlebar grips in summertime, what's not to like about it?

But the bike-sharing app is a different story.

Granted, some of the problems I have with it come from my inability to read the Chinese messages it shows when for some unfathomable reason it won't do what it's made to do－unlock bikes.

Still, it does seem riddled with peculiarities.

The mostly clear summer skies we had this year bring one immediately to mind. In bright sunshine, it's difficult to clearly see the screen of your phone. When the app, for reasons only it understands, throws roadblocks into the process of unlocking a bike, that becomes a problem. If you don't react appropriately, you don't get a bike.

Contrarily, at nighttime, if you try to unlock a bike in dark surroundings, it can't read the QR code. When that happens, the light on my phone automatically switches on to help the scan, but the app apparently finds the light too bright and endlessly scans the QR code without success.

So let's recap. The app has features that, at least in my hands, impair how it works in the daytime, and it has other features that impair how it works in the nighttime.

But who's complaining? The rest of the time it's just fine.

I've learned a few tricks along the way, like finding a bike at night that's directly under a streetlight, which sometimes helps, or seeming to give up and walking away after a few fruitless attempts and then unexpectedly returning to try again. My success rate has improved to a little less than 50-50.

I keep thinking about the perseverance and ingenuity Turing and his team showed in conquering the Enigma machine. Maybe I can learn something from them.

But for the time being, the bike-sharing app remains for me an enigma.