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

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

Summary: 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.

TOPICS: Mobility, Apple, Hardware, iOS

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.

See also:

Topics: Mobility, Apple, Hardware, iOS

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  • Duh

    All systems run slower when they do more things than they used to. This has nothing to do with iOS.
    Sean Foley
    • Features are iOS-related and there are other factors which affect iOS ...

      ... in ways that Windows (and Mac OS X, and UNIX/Linux) are not affected. A long time challenge for operating system designers is "fragmentation" and "garbage collection". In order to utilize storage space most efficiently, when apps are added to, or removed from the device, storage gets fragmented.

      A pre-emptive multitasking system (like Windows, Mac OS X, or UNIX/Linux) uses idle time to perform these chores. Power-sensitive operating systems like iOS and Android don't bother with these chores. SSD technology helps but does not entirely address the problem.
      M Wagner
      • a little knowledge is a dangerous thing

        iOS operates the SAME preemptive Unix based multitasking operating system as MacOS and it's file system does not rely on idle time processes for storage defragmentation.
        Henry 3 Dogg
      • As they say, speak for yourself

        No typical UNIX OS, such as OS X or iOS (the very same OS, by the way) does any filesystem defragmentation, because UNIX filesystems are designed to not need any.

        Unlike Windows.

        Oh, and by the way, "preemptive" and "idle time" have nothing in common, nor does any of these terms relate to filesystem (de)fragmentation.
  • And.

    This is where you find that this "Hellstew of vulnerabilities" in Androids fragmentation does make a little sense.

    Having older Android devices happily running on older software keeps them happier to run for longer.

    Vulnerabilities don't seem to be much of an issue for people who just want a decent phone for 2 years, with some internet access.
    • Older Android devices

      I almost always buy older model Android phones to gain a significant discount. I know that even if the vendor no longer supports the device, I can root and mod it with the latest OS and gradually control the processor, UI animations, etc. My daughter is using my 4 yo HTC and it is still running fast with the latest OS and apps.
      Rann Xeroxx
    • When it comes to smartphones, it is as if there is colusion between ...

      ... carriers and manufacturers. There is no reason why a smartphone has to be limited to two years but carriers make it so simple by inflating the upfront price of the device and then offering what seems like steep discounts on already artificially high prices on the hardware.
      M Wagner
      • no trick here

        The carriers could care less about the device cost or device profit: what they sell is the *service* and they make enormous profits (in percentages) there -- not on financing the devices.

        The device subsidy exists in order to lure you and (if possible) lock you in using the expensive service.
  • All phones

    eventually slow down as their respective OSs are updated to the latest version. Funny thing is my 4 year old iphone 4 is as fluid, and in some cases more so, than my Galaxy S5.
    • Four year old iPhone 4

      I have a four year old iPhone 4 and it was as fluid as a door stop after I upgraded to iOS 6. The problem seems to be insufficient RAM, not processing power. Switching between tasks always makes it stutter. However, if I switch between two tasks and then switch back and forth between just those two tasks, it's very fluid. Just don't switch to a third or fourth task and then expect either of the original two to be fluid until they get swapped back into RAM.

      Now my iPhone really is a door stop because last January I couldn't stand it anymore. I bought a Nokia 520 on a fire sale for $50. Except for the various Windows challenges, it was a good phone. After I updated it with Windows 8.1, it now behaves worse than the iPhone 4. Cortana's voice sputters and spurts when I first access her. Voice recognition often misses the first several words if not the entire sentence. Same problem with car integration. First call is missed. Second call works. After whatever I want gets swapped into memory, it works great. However, just like the iPhone, if you switch between too many apps, it doesn't have enough memory and it starts sputtering again.

      Regarding performance, either phone is decent as long as what it's running is in RAM. To me, this seems just like the PC era when Vista debuted and folks tried to run it with 512MB or 1GB of RAM. Vista was a pig (7 too) and likewise, the phone OSes are fat and getting fatter.

      Call it whatever you want but it's by design and I'll never be convinced otherwise. Consider the new replacement for the Nokia 520. Want to guess how much RAM it has? The same as the 520. It's immediately going to be obsolete. Shame on Microsoft since they are releasing what will perhaps be the most popular product and it will provide a very poor experience for many who will obtain this phone as their first Windows phone experience.
      • Buying more RAM up-front will always "buy you" a longer device life.

        If 16GB is ENOUGH for two years, then buying the 32GB model ought to give you three or four years worth of performance. (Unless Apple is being as devious as Adrian seems to suggest.) of course, the absence of a removable/replaceable battery still keeps you from holding on to your device forever.
        M Wagner
        • a little knowledge is a dangerous thing [again]

          There are no smartphones on the market with 16GB or 32GB of RAM.

          The 16 GB and 32 GB models that you talk of is flash storage i.e. Disk equivalent.

          Apple makes no phones that need to be retired because they don't have a replaceable battery.
          Henry 3 Dogg
          • By the way

            The iPhone battery is easily replaceable. Most places that sell the spare batteries also sell the required (screwdriver) tools.

            Of course, normal people will just visit the Apple Store to have their battery replaced.
  • Its all a racket

    Seriously ask yourself if your phone is faster as far as content consumption as it was 5 years ago. I have been duped into upgrade after upgrade, and yes, my phone can do more with each generation of device; however, it does not do anything faster. Video still lags, I still can't browse local networks, the camera is still sub-standard, the phone call quality is not better. So basically the ability for it to add small tasks, integrations, and features are all that its doing. Think hard about putting any money out for an upgrade, the market has peaked in phone technology.
    • You could call it that (because planned obsolescnce is real) but ...

      ... from the OEM's perspective, how can they keep innovating if they don't have a steady income and repeat customers? On the other hand, Moore's Law still applies. Processors double in speed every 18 months so the smartphone you buy today will be twice as powerful as the smartphone you bought two years ago.

      Now, if all you need is a basic cell phone for talk and text, all you need is a cell phone with a removable battery. Both are extremes. Carriers need so many $$$ per customer so they price their products so that they can get you to pay to hit that "sweet spot". You can shop around and find whatever you want but there are always trade-offs.
      M Wagner
  • Don't agree

    My iPhone 5 runs as well as it did the day it was new two years ago. Android phones, on the other hand, definitely slow with age. My wife's phone is almost unusable, and it's only slightly older than my iPhone. She'll probably go with an iPhone when the new ones are announced.
    • you are comparing a phone to

      and OS that can be installed on anything. Please compare to a specific phone. It gets me when people just say "android" this and that. My nexus 5 and 4 still run perfectly so I don't know what you are talking about.
    • Start up manager

      The only reason a Android phone in general would slow down is an update to the OS that the hardware can't run (if you are running the latest kitkat with ART, it should actually run faster) or something in the startup that is running. Install a app startup manager and kill anything that should not be there.

      Android's power is also its biggest problem and that is being able to multi-task and run custom services in the background.
      Rann Xeroxx
  • Where else would you buy a new laptop or desktop every 2 years and blame...

    Who else would you buy a new laptop/desktop every 2 years and blame the OS for having to do so?? Only the iSheep idiots. BTW, no other iPhone has NFC. Talk about fragmentation. Cost of NFC to have been included to iPhone 5s or 5c? 10 cents. iSheep idiots
    • Actually...

      ...as far as laptop/desktops previously, it would have been Microsoft that would bloat up the OS with each iteration until the Vista debacle.
      Rann Xeroxx