Wesley's Tool-Box

Shortly after finishing the battery tests for the earlier post, iPhone 4S and later generations received the iOS 9.1 update. Then the thought crossed my mind that I should have tested the "Low Power Mode" introduced with iOS 9. It's a feature touted as enabling you to use the phone up to an hour more by cutting off some background activities, reduce the screen brightness, and slow down the processor. Would it equally benefit different generations of the iPhones? I ran the GeekBench 3 again to find out.

Here, the only major differentiating factor would be the processor speed because the iPhones were in airplane mode and the screen brightness was manually set to lowest like the previous tests. I did re-run the tests for the 'normal' mode because the iOS version was changed from 9.0.2 to 9.1. And as always, the values are normalized to the designed battery capacity.



This revealed that Apple's claims were not overblown. With the exception of iPhone 4S, the iPhones indeed lasted significantly longer under Low Power Mode: about one and a half hours with 5 and 5S, and about two and a half hours with the Plus phones, which are around 30 to 50% gain. It seems that the processor is clocked down to squeeze out as much battery time as possible. On the other hand, the processor for 4S can't seem to throttle back for this mode, resulting in practically no changes. This means that for 4S, the real-life battery savings would have to come from other tweaks.


And if we measure how much work is done with each mode, it gets more interesting. It confirms that the 4S isn't doing anything different, while iPhone 5 seems to fully trade battery time for speed. Meanwhile, the newer generations are able to do more work under the Low Power Mode. This means that if the tasks you do a lot on your phone isn't impacted too much by this mode, it might not be a bad idea to keep this mode on while you do those things if you want to maximize battery life.

Battery life is something most smartphone users take a big interest in, sometimes more than the raw performance. What good is a fast phone if you can't use it long enough without recharging? For iPhones, this is especially important because you can't swap out the battery without disassembling. So I decided to test this as the time allowed.

Now, each of my iPhones had been used for wildly different lengths of time, so the level of remaining battery capacity would be different as a result. This would obviously affect the tests, so I checked the capacity using iBackupBot, as you can see here.


Fortunately, batteries were mostly in good condition, having 90% or more capacity left. The brand new iPhone 6S Plus actually had slightly more than it should. Still, the difference is non-negligible. So the results of my battery tests would be normalized to the design capacity to make the comparisons fair. The 6S Plus results would be lowered a bit while the others would be boosted, all according to their respective ratios.

For a heavy-load scenario like playing a game, I used the battery test included with GeekBench 3. This is available for version 3.3 and higher, so iPhone 4 and 3GS, which can only run lower versions, had to be left out. With this test, airplane mode was turned on and the low power mode was turned off. To see how much effect the display backlight has, the test was run with both lowest and highest brightness settings.



With the screen brightness lowered, iPhone 6S Plus pulls ahead of all other previous generations. It's an impressive feat, beating the 6 Plus at the second place by about two and a half hours. The gap significantly narrows with full brightness, but it still manages to stick around slightly more. Considering that this is done with 5% less design capacity, it's certain that the 6S Plus is quite efficient despite all the enhanced performance.

Meanwhile, the battery capacity of the Plus series is so large that it has enough power left over even after driving a bigger backlight and much more screen pixels. Overall, the Plus series lasts noticeably longer than the predecessors. Curiously, the 5 and 5S don't show much difference in regards to the screen brightness compared to the other models. It seems the characteristics of the screen used for these devices were different.

Apple Watch's Korean launch is just a few days away (June 26) and I'd like to offer you a nicely consolidated list of all my reviews for your convenience. I hope this will help you get some idea on whether you should get one and how you should use it if you do.

Preview	Summary
	1. One of the first Apple Watch in Korea
	Sent three days after the official release in the US and arriving about a week later, one of the first Apple Watch to land in Korea gets prompt unboxing and gets ready for a full review.
	2. Getting the Apple Watch up & running
	I have the bands installed in place and the battery wirelessly charged up, so that I can pair the Apple Watch with my iPhone 6 Plus and make it work.
	3. Basic screens & buttons of the Apple Watch
	Apple Watch's many screens are explored, including the watch face, lock screen, home, and favourites. I also try out the digital crown and the side button.
	4. Notifications & contacts on Apple Watch
	As one of the primary functions, I took a look at how the notifications appear and interact. Then I tried contacting someone with Apple Watch, either through text or voice.
	5. Apple Watch's daily life tracking
	Fitness tracking with Apple Watch is explored, including the heartbeat measurement with an integrated sensor and the daily activity logging through a three-ring system.
	6. Running, swimming with Apple Watch
	I had both Nintendo Wii Fit Plus and Apple Watch record indoor running sessions to see how they compare. Then I went swimming with my Apple Watch to see if it'd actually work.
	7. Apple Watch as an extension, stand-in
	I tried using Apple Watch as a replacement for membership cards. Then I remote controlled my Apple TV and iPhone 6 Plus camera with it, as well.
	8. Battery life of the Apple Watch
	I recorded my Apple Watch's battery life for three weeks, through international travels and all sorts of exercises, to see if Apple's claims stood up.
	9. More Apple Watch observations
	I took a look at how fast the Apple Watch charges up and how step counting data are consolidated. Also, I have some more tips and observations on its daily use.
	10. 45 days with Apple Watch & watchOS 2
	Seven weeks later, the hardware of Apple Watch Sport is still standing up quite well. But early watchOS 2 and iOS 9 betas are incredibly rough to use.

1. Charging Speed

I knew that my Apple Watch gets charged in about two hours, but I couldn't do charging test because it's rare to see it drained to 0% on normal use and I was collecting battery use data for the first three weeks. Now that this was done, I induced the watch to drain until it went into Power Reserve mode as it hit below 1%. Then I put it on the charger to see how it went back to 100%. During the time, no notifications were received by the watch and the only time the screen was on was when I checked the charging status every 5 minutes.

Apple's official document claims that a (38mm) Apple Watch would charge up to 80% in 1.5 hours, and take another hour to hit 100%. In testing my 42mm watch, it charged to 82% in 1 hour 20 minutes, getting about 5 to 6% charged every 5 minutes. 37 minutes later it became fully charged, taking slightly less than two hours (1 hour 57 minutes) total. Perhaps Apple's estimates were conservative.

Seeing as I generally have 20 to 30% of battery left when I charge it daily, this means I can put my watch back on after about an hour and a half of charging. Less downtime is good.


2. Water, Cleaning, & Touch Screen

In the first two weeks of use, I didn't let my Apple Watch touch flowing water. I simply wiped off any dirt or sweat with a cloth. Interestingly, the digital crown began to feel sticky. It used to be that it would effortlessly spin when touched with a finger, but this was not the case anymore.

Seeing that the device was water resistant, I thought it would make sense to clean it with water to resolve the situation. And indeed, after a light dip in the running tap water, the stickiness was gone. To prevent any future occurrences and for good hygiene, I have the watch washed at least once daily these days.

As I wash the watch, the flow of water onto the touch screen usually turns the screen off. But occasionally the screen gets turned back on and certain flows of water get interpreted as finger touches, resulting in unintended button pushes or swipes. This seems to be the culprit of a minor annoyance when swimming with the Apple Watch. Midway through a swimming session, it sometimes decides to stop logging, and an errant press on the (X) button on the screen might have happened.