Apple's iOS 9 is set to become the most downloaded software update in the company's history. Almost 50 percent of capable iOS devices have installed the new operating system since its release last week, Sept. 16.

"iOS 9 is off to an amazing start, on pace to be downloaded by more users than any other software release in Apple's history," vice president of Apple's marketing department Phil Schiller said via Wired.

If you're one of the millions who has already adapted to iOS 9, you might be wondering how you can improve your iPhone's efficiency as well as save up on those precious battery juices. Luckily, you can do so by enabling the software's new "Low Power Mode" option.

Users should bear in mind though that Apple's new operating system, on its own, can already do wonders for iOS devices.

According to the tech giant via Apple Insider, iOS 9 will run more efficiently and smoothly compared to previous builds since it contains system-wide changes. The "Low Power Mode" option merely prolongs the already optimized iOS 9 device.

The new feature doesn't even need to be manually enabled. Once an iPhone has 20 percent battery life left, users are immediately notified to enable the feature. The automatic prompt will again resurface once battery life is down to 10 percent. Users who want to turn on "Low Power Mode" in advance can do so by enabling it manually.

To do this, users should navigate through the Settings app then select the new Battery menu wherein a switch for "Low Power Mode" can be found.

Upon activation, users should notice the battery indicator on the top right corner of the screen turning yellow. The yellow indicator signifies that the iPhone is running in a more efficient state.

Needless to say, some visual effects and secondary features will have to be disabled to prolong the iOS 9 device's battery life. This is exactly what the "Low Power Mode" will do. It will recognize and reprioritize apps usage. The new feature will disable unnecessary performance capabilities such as automatic downloads, background app refresh, mail fetch and several interface animations.

Meanwhile, iOS 9 users might be delighted to know that Apple is already busy developing the first update to their latest operating system.

Latin Post reported that iOS 9.1 will feature more than 250 new emoji such a burrito, taco, unicorn head, and several hand gestures including a middle finger.