When I sat down to ponder possible killer features for the next wave of smartphones, one idea would make bulky batteries a thing of the past. "Why doesn't your regular old LCD screen double as a solar-powered charger? That technology has been around since 2007," I mused. "There's no reason your phone couldn't get a power boost every time you do the Macarena, like that wristwatch you haven't worn since 2005."

And you know what? Apple (AAPL 1.27%) is actually working on exactly this.

Apple Insider ran across a patent filing from Cupertino where the inventor describes a "shake to charge" apparatus for mobile electronics. By shaking a small magnet (or several) across one or more copper coils on a printed circuit board, the system would generate electric energy.

The patent application doesn't explore how much power might be produced this way, or whether it's enough to keep your smartphone charged throughout a day of average physical activity, but it's definitely a step in the right direction.

Depending on the power efficiency of the final product, this could be a bigger game-changer than the inductive charging solution that Nokia (NOK -0.81%) just introduced. If walking to your commuter train with the phone in your pocket is all you need to keep the gadget functional all day long, it seems almost silly to even set up a wireless charging station.

The battery is typically the largest component inside today's smartphones, with only the screen claiming a comparable chunk of three-dimensional real estate. Just imaging how thin the next iPhone might be if the battery was half the size, relieved by an innovative extra-charging solution like this one. At some point, we'll be able to slice tomatoes or shave with the edge of the case.

I'll leave it up to you to decide whether that's a good thing or not. But it's obvious that today's amazing smartphones still have a long way to go before reaching absolute perfection. Apple is going to need to stay vigilant and adjust its designs to meet consumers' needs. In our latest premium research report, our analysts have dissected the tech giant from every angle, giving you the opportunities and risks that Apple faces. For less than a week's worth of coffee you too can gain an investing edge. Click here to get this premium report on Apple.