Why your iPhone or iPad feels like it's getting slower

No, Tim Cook doesn't have a switch he can flip to makes old iPhones and iPads run slow when he's about to unveil new hardware.
Written by Adrian Kingsley-Hughes, Senior Contributing Editor

Over the years I've come across a lot of people, some of them otherwise very level-headed and sensible, who think that Apple – for some reason it's almost always Apple that's accused of this – can deliberately and maliciously makes existing iPhones and iPads run slow, thus forcing people to upgrade.

The idea goes something like this. Buried deep in every iPhone or iPad is some code that's waiting for the day to come when Tim Cook, deep in his secure bunker, flips a switch, which in turn beams a signal to every existing iDevice on the planet to activate the "molasses" mode.

People get frustrated with their old iDevice, and promptly go out and buy a new one.

Yeah, OK, this is crazy talk. File it with the Bigfoot reports and the tinfoil from Roswell, right?

Well, there is a part of this that is true, and that's the bit about iPhones and iPads getting slower over time. This does happen, and there's a very sound and logical reason for it.

When Apple builds an iPhone or iPad, it has to finely balance battery power, performance, usability, and price to end up with a device that is powerful enough to run apps well, yet deliver good battery life and not end up costing the fortune. That's tricky, but since Apple knows that operating system that device is going to run, and controls what operating system are going to be released, it can craft a situation where that device has a lifespan of around three years or so before becoming obsolete.

This is called planned obsolescence and it's not a new thing. And believe it or not, it doesn't just relate to iPhones and iPads, but cars, PCs, software, and much more.

So, if Tim Cook isn't flipping a switch to make your iDevices feel old and sluggish, let's take a look at what's actually behind it

iOS updates

iOS updates, especially the major updates, bring new features to existing devices. But these new features come with a performance overhead that the old operating system didn't place of the hardware.

If there weren't this pressure, Apple could use the same processor to power its devices for several iterations.

Throw a couple of major iOS updates at an iPhone or iPad, and it's expected to do a lot more than it was the day it was pulled out of the box.


Over the course of the lifespan of an iPhone or iPad the apps that the hardware runs are coded to do more. None of that comes free, and it has an impact of factors such as performance and battery life.

Also, apps are subject to bugs that can can have an adverse effect performance and battery life.

Battery degradation

Every time you recharge the battery in your iPhone or iPad, you wear it out a little.

According to Apple, the iPhone "battery is designed to retain up to 80 percent of its original capacity at 500 complete charge cycles" and the iPad "battery is designed to retain up to 80 percent of its original capacity at 1000 complete charge cycles." A complete charge cycle is taking the battery from flat to full, and so two recharges from 50 percent to 100 percent is one full recharge.

If you go through a recharge cycle daily, then in a little over a year the iPhone will only be capable of holding 80 percent of its power it could, and after a couple years it will be down to under 60 percent capacity, and the owner might be thinking about an upgrade.

A worn out battery doesn't make the iDevice slower, but it does affect how long people can use their iDevice before having to find the power cord.

Bottom line

The bottom line is that you iPhone and iPad are getting slower because you're using them, and new iOS updates and new apps allows you to squeeze the last drops of performance juice out of your old hardware thanks to good design. After all, remember that Apple could design the iPhone and iPad in such a way that you'd have to replace them every year if it wanted.

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