Everything You Need to Know About Batteries in Your iPhone, iPad, and Mac

If there’s one thing we need to use our mobile devices and computers it’s power. Without it, these devices are just bricks. Managing power on mobile and portable devices has long been a balancing act between performance and comfort. You don’t want to cripple your devices by turning off too many useful features, but, depending on how you use your mobile devices, you may need to stretch the battery life as long as possible.

In this article, I’m going to tell you how batteries work on Apple devices, how long they last, how to optimize your battery use, when to use low power mode, and when to get a new battery for your iPhone, iPad, or Mac.

Read the rest of the article on The Mac Security Blog.

Managing Battery Life on Macs and iOS Devices

Batteries are essential to our portable devices. For many of us, in our everyday use of Macs and iOS devices, we don’t have to worry too much about this. Modern iPhones and iPads provide a full day‘s battery life, and if you use a portable Mac, you can probably get through the day unless you are using battery-intensive apps.

But sometimes you can’t. If you’re away from home or the office for a long time, you either need to take a portable battery pack with you, or carry a charger and go hunting for available plugs. And, as your devices get older, their batteries lose capacity. This means that instead of, say, a full day of power for your iPhone, you may need to charge it sometime in the afternoon.

In this article, I’m going to tell you how you can check on your battery to see what its capacity is, and how to find which apps use the most power so you can get rid of them to ensure that your devices’ batteries last as long as possible.

Read the rest of the article on The Mac Security Blog.

Access the New Battery Health Setting in iOS

Battery healthApple added a new Battery Health feature to iOS 11.3, which was released yesterday. This gives you information about how good (or not) your iPhone’s battery is. This is in response to issues around iPhones being throttled if their batteries are old.

To access this setting, go to Settings > Battery > Battery Health. You’ll see the battery’s maximum capacity – the amount of power it can hold when fully charged – and its peak performance capability; this latter will be reduced if the battery is old.

This information shows up on my iPhone 8+, but not on my 10″ iPad Pro, or my iPad mini 4. My guess is that it only displays on those iPhones whose processors can be throttled if their battery is below nominal capacity. (iPhone 6 or later, and iPhone SE.) It would be useful, however, if it displayed on all iOS devices; I think users of old iPads might like to know what the maximum capacity of their batteries is, and potentially replace the battery when it gets low.

Poor MacBook Battery Life Caused by Time Machine?

My MacBook is my second computer, and I don’t use it much. I use it for testing, for taking screenshots, and for working outside my office from time to time. I’ve been using it a lot in the past week, and I’ve noticed that I’m getting perhaps 6 hours of battery life, without using a lot of apps.

One thing I notice is that two processes, mtmd and mtmfs, pop up frequently, using about 100% of CPU (of a core) and do so for a while. Here’s a screenshot from iStat Menus when that happens:


These two processes are related to Time Machine, and have something to do with creating local snapshots. But I’m only using the MacBook at my home office, so it’s on the network where my Time Machine backup device is located, and it shouldn’t make local snapshots. It should only do this when it can’t access your Time Machine disk; it then copies those snapshots the next time the Time Machine disk is available.

When I check Activity Monitor, and look at Energy, the app listed as having the highest impact is Time Machine, way above Safari which is the second. So it’s clearly Time Machine that’s killing my battery.

Activity monitor

I’ve contacted AppleCare, and spent a lot of time on this, sending them logs and other data, and I’m waiting to hear back. I reinstalled El Capitan, and nothing changed. Is anyone else seeing this?

Update: I found the following in system logs. I find these entries to be interesting.

12/7/15 18:32:47.000 kernel[0]: Sandbox: mtmfs(552) System Policy: deny(1) forbidden-rootless-xattr
12/7/15 18:32:47.156 mtmfs[552]: could not set attributes com.apple.rootless on destination file descriptor: Operation not permitted: Operation not permitted

12/7/15 19:33:33.810 com.apple.xpc.launchd[1]: (com.apple.mtmfs) Unknown key for Boolean: ForceEnableHack
12/7/15 19:33:33.810 com.apple.xpc.launchd[1]: (com.apple.mtmfs) This service is defined to be constantly running and is inherently inefficient.