If you're still using an iPhone that's two or more generations old, the chances are that it isn't as nippy as it used to be. The interface seems more sluggish, apps take longer to open or run - it just isn't the swift device you remember. Maybe it's been performing more slowly since you installed iOS 7. But there are some techniques we can use to speed up an ailing older iPhone. Whether you're on an iPhone 3GSiPhone 4, iPhone 4S or iPhone 5, you can benefit from our speed tips for older smartphones. 

Apple's iPhone 5s is its flagship smartphone, though it's soon to be replaced by the iPhone 6, but older models remain popular: the iPhone 4S is still sold by Apple as budget alternatives, and plenty of Apple fans continue to use a beloved iPhone 4, iPhone 3GS or even older iPhone.

But is your iPhone still performing? All computing devices are prone to slowing down over time, as their memory fills up and extra software is installed, but the way iPhones use their memory makes them less prone to this than most.

It's possible that it just feels slower than it used to, because you've got used to what initially seemed dazzlingly quick operation, or have started to compare it to friends' newer, faster models.

But sometimes it's possible to make a direct comparison: when there's an app you used to enjoy but has since become unusably juddery. Such a situation is what led us to write this feature. The wonderful, super-fast game Super Hexagon demands lightning reflexes to survive, but the stuttering graphics on our iPhone 4 now make it impossible to play. We've also been seeing problems with the iPhone 4 handling Temple Run 2.

Here are some great methods to speed up an iPhone 3GS, iPhone 4, iPhone 4S or even iPhone 5, iPhone 5c or iPhone 5s, if you're not happy with the way it's running.

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How to speed up an iPhone: Is your iPhone up to date?

Apple's most recent operating system for the iPhone and iPad, iOS 7, divided opinion. We think it's great, but we're the first to admit that it can be difficult for older iPhones to run - with the result that iPhone 4 owners have found performance has dipped since upgrading. (The iPhone 3GS and earlier aren't compatible with iOS 7 upgrades at all.) This is one of most common recent reasons people seek to downgrade from iOS 7 to iOS 6, in fact, but that is unfortunately a difficult process.

If performance is your main bugbear with iOS 7, however, fear not; because Apple claims that the newest update of all, iOS 7.1, solves many of these issues. (It also, as you can see below, softens the 'toxic chemical spill' greens in certain icons.)

Upgrade from iOS 7 to iOS 7.1: new colours

We wouldn't recommend iPhone 4 users to upgrade from iOS 6 just for this new update, but if you've taken the plunge and regretted it, iOS 7.1 is a great option for recovering some or even all of your lost performance.

Our anecdotal experience with an iPhone 4 that's updated to iOS 7.1 is cautiously pleasing. Don't expect miracles or an iPhone that feels 'like new'. But apps and app folders open more quickly and certain apps like Twitter and Facebook seem to take less time to get past the opening blank screen. In many cases Apple has achieved this by tweaking or simplifying interface animations.

Ars Technica has measured the comparative speeds opening native apps in iOS 6, iOS 7 and iOS 7.1, and found tangible speed boosts from the second to the third; although, somewhat frustratingly, most of these times were still some way off those recorded in iOS 6.

How to speed up an iPhone: Shut down all open applications

Let's start with the easiest solution: closing down all non-essential apps. The way multitasking is handled (or rather not handled) in iOS 6 means they shouldn't be hogging the RAM to any significant extent, but it can't hurt.

Double-click the Home button to bring up the tray of currently running apps along the bottom of the screen. Press and hold any of these icons until they all start wobbling, then start pressing the red minus signs to close them down. We've going to close down everything, then start again from scratch.

How to speed up a slow iPhone

In iOS 7, double click the Home button to see all of your open apps and then swipe upwards to close them. You can swipe with up to three fingers to speed up the process a little bit. Irritatingly, there's no way to close them all at once.

How to speed up an iPhone: reallocate the memory

The iPhone 5s has 1GB memory, but older phones have even less. Apple doesn't make reallocating this RAM type memory easy but there is a way you can do this and therefore speed up your iPhone.

Download the free Battery Doctor app. We use this primarily to reallocate our memory on our iPhone 5. If you find that you're using up lots of memory, tap 'Boost' and watch as the app reallocates the memory and helps speed up your 'Mobile Speed'.

Whenever our phone slows down this is the first thing we do.

Hopefully Apple will make the memory handling better in the future.

How to speed up an iPhone: Clear your Safari cookies and data

Let's try emptying Safari's data, cookies and so on to free up some memory.

Open the Settings app and scroll down to Safari (it's the last in the fourth set of options on both iOS 6 and iOS 7). Here you can choose Clear History and Clear Cookies and Data. (Bear in mind, though, that Safari will no longer suggest URLs as you type, unless they're bookmarked. And clearing the data may mean some websites forget your preferences.)

How to speed up an iPhone: Restart

Let's restart the iPhone completely. Press and hold the Sleep button (the one on the top right of the iPhone) until the Power Off slider appears. Swipe it and wait for the iPhone to power down.

Once it's finished (it'll take about 10 seconds or so), start the iPhone up again by pressing and holding the Sleep button for about 5 seconds. You'll see the Apple icon for a minute or so, then the iPhone will restart.

You shouldn't have to do this very often, but when you do it'll clear out the memory space and can often fix unruly apps. The occasional power cycle helps keep iOS ticking over.

How to speed up an iPhone: Kill automatic background processes

Getting rid of automated features will help keep your iPhone running faster in iOS 7, and help extend your battery life as well. If you're running iOS 6, you can skip this step as Apple didn't introduce these features until iOS 7.

Turn off Automatic Downloads. Tap Settings > iTunes & App Store > and turn Automatic Downloads off. If you spend a lot of time uploading Music, Apps and Books you might want to turn off those as well.

Turn off Background App Refresh. Tap Settings > General > Background App Refresh. Turn Background App Refresh off and tap Disable Background App Refresh.

Both of these are luxury items. You don’t need them and you’ll see a big boost in battery life as well as a noticeable increase in performance.

How to speed up an iPhone: Turn down the graphics

Again, iOS 6 users can skip this step because it only relates to iOS 7, which introduced some fancy new visual effects.

Turn off Motion. Tap on Settings > General > Accessibility > Reduce Motion and set Reduce Motion to On. This turns off the parallax effect of icons and alerts (many people find it easier to use in this setting).

Increase Contrast. Tap on Settings > General > Accessibility > Increase Contrast and set Increase Contrast to On. This disables the see-through background effects, which speeds up iOS 7. It’s most noticeable on Control Centre which will now have a solid background and should work much faster.

Both of these will help with battery life, but are especially helpful for speeding up iOS 7.

How to speed up an iPhone: Delete text messages

We'll continue on our quest to free up memory by going through the Messages app and deleting everything that we don't need to save.

Open Messages and scroll down to find any message threads that you can manage without. Swipe to the right and tap Delete. Alternatively you can tap Edit and tap the red minus buttons to delete unwanted threads.

How to speed up an iPhone: Delete unnecessary songs, photos and videos

Okay, let's get serious and free up a lot more memory. Open the Settings app, then tap General, and Usage. You'll see how much storage space is left and which apps are using up most of the space.

If you're anything like us, the top two culprits will be Music and Photos & Camera, because these apps' storage usage includes music, images and videos. We'd suggest keeping at least 1GB free just to make sure there's some free space for iOS to shunt files around without having to do too much juggling.

Open the Music app and find the non-vital track, album or artist that you want to delete. Swipe to the right and press Remove (or 'delete' in iOS 6).

How to speed up a slow iPhone

Plug the iPhone into the Mac and open Image Capture (assuming you've not set it to open automatically when it detects an iOS device). Tick the option 'Delete after import' at the bottom left.

Click the photo you want to copy across, or select multiple consecutive photos using the Shift key, and drag and drop them into a folder on the Mac. You'll see a green tick appear next to them in Image Capture, to show that they've been downloaded.

If there are any photos on there that you don't want to keep but still want deleted from the iPhone, select them and click the red circle at the bottom. Image Capture will confirm you want to delete the photo.

Of course, you can also delete photos on the phone itself. Open the Photos app, find the images you want to delete, tap 'Select' and then tap on the images you want to delete. The tap the bin icon and confirm to delete the photos and videos you've selected.

Speed tips for slow iPhones continues on next page >>

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