Apple isn’t counting on gaming to be the killer app for the Apple Watch, but that doesn’t mean the new wearable won’t catch on with commuters who need to kill an hour or so or ‘tweens looking for a new addiction. A quick glance at the App Store shows there are already dozens of titles, from puzzlers like “Snappy Word” to action titles like “Watch Quest,” vying for space on the device's tiny screen.

Some are merely just miniaturized versions of their iPhone counterpart. Others are modern-day Tamogotchis -- or virtual pets -- that users play for seconds at a time. The point is that gaming on the Apple Watch will be a very different experience than playing on anything that’s come before it. That’s not necessarily a bad thing, but there are some caveats.

Design experts say most games that will succeed on the Apple Watch will have some things in common. The devices’ 38 or 42mm screen sizes, depending on model, make it difficult, if not impossible, to play games that feature lots of moving images or require precise input – think Angry Birds. On the other hand, it could be great for games that take a series of sequential moves over a set time period.

Users can easily pick up a smartphone and play for hours. But the smartwatch demands shorter spurts of attention -- seconds at most. Even Apple reinforces this notion within its app design guidelines. “If you measure interactions with your iOS app in minutes, you can expect interactions with your WatchKit app to be measured in seconds,” Apple’s Human Interface Guidelines read.

Newzoo Global Games Market 2015 Games on smartphones and smartwatches are expected to account for over 22 percent of the global games market, according to market research firm Newzoo. Photo: Newzoo

For gaming on the Apple Watch to succeed, developers will have to carefully design their offerings around the watch’s limitations or come up with new concepts entirely. Casual games that are often played during a commute or while waiting in line could find a home on the Apple Watch. That could include small puzzles that don’t rely on graphics or sophisticated content. “Those are the kinds of things that are more likely to take off,” said Mark Griffiths, director of the International Gaming Research Unit at Nottingham Trent University.

Developers could go down another route by gamifying fitness and health apps, taking advantage of sensors such as the accelerometer and heart rate monitor to integrate a wearer’s movement into gameplay. Some games, such as the space adventure title “Walkr,” try to do this by using daily step data as an in-game currency.

Many Apple Watch games are variants of their iPhone cousin. But some developers are creating games solely with the Apple Watch in mind. One such example is “Runeblade,” a free-to-play fantasy adventure developed by Everywhere Games. Unlike many apps that use the iPhone as an extension, “Runeblade” gameplay happens primarily on the watch, with the iPhone app serving more as a companion.

“We’re getting a lot of positive feedback from the players,” said Everywear Games CEO Aki Järvilehto. “What seems to be especially compelling is the combination of short five to fifteen-second gameplay sessions combined with longer term objectives. And that’s what we set out to deliver -- a fantasy adventure which is always available and ticking on your wrist even when you are not looking."

Runeblade "Runeblade" is a fantasy adventure game designed exclusively for the Apple Watch. Photo: Everywhere Games

Still, the fleeting nature of interactions on Apple Watch doesn’t provide much time for developers to get players hooked or addicted to an Apple Watch game. “Addiction is about constant reinforcement and constant rewards,” said Griffiths. “If the rewards don't come thick and fast, then it may not become a habitual behavior.”

That’s not the only headwind for Apple Watch gaming. Currently, Apple only allows its preinstalled apps to run natively on the Apple Watch, leaving all third-party apps to run wirelessly from the iPhone. The effect is hardly noticeable on small apps, but for large apps and games this can sometimes create slow load times and a sluggish experience. This may not last for long, as Apple plans to introduce native third-party app support for the Apple Watch later this year.

Personal screen gaming, including on smartphones, is expected to grow to $20.6 billion this year, up 21 percent from last year, according to Newzoo projections. Gaming has found its way onto virtually every major personal computing platform, from the PC to the iPhone. Don’t expect the Apple Watch to be any different.