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 aniPhone 3GS, iPhone 4 or iPhone 4S - or even something earlier - you can benefit from our speed tips for older smartphones. Updated 11 March 2014

Apple's iPhone 5s is its flagship smartphone, 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 4 or 3GS 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, 5c or 5s, if you're not happy with the way it's running.

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How to speed up an older iPhone: Install iOS 7.1 (if you're on iOS 7)

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 just 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 older 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

How to speed up an older iPhone: reallocate the memory

The iPhone 5 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 Saver app. We use this primarily to reallocate our memory on our iPhone 5. It will show you how your 'Mobile Speed' is running. If it is running slowly, Tap Mobile Speed, watch as your phone shows how much memory is being used, and then tap Reallocate Memory and watch as the app reallocates the memory.

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

Hopefully Apple will make the memory handling better in the next version of iOS.

How to speed up an older 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). 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 a slow iPhone

How to speed up an older 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.

How to speed up an older 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 older 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. Considering that we've only got 485MB free out of 16GB, it's worth trimming this down.

Open the Music app and find the non-vital track, album or artist that you want to delete. Swipe to the right and press Delete.

How to speed up a slow iPhone

For photos and videos, we're going to plug the iPhone into our Mac and use the pre-installed app Image Capture. (For more on using this, see our article 'How to transfer photos from your iPhone to Mac'.) This will allow us to copy the photos we want to keep on to the Mac for safekeeping and backup, and delete them from the 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 an image you want to delete and tap the bin icon at the bottom right. If the bin's not showing, tap the photo itself to bring up the various options.

Pruning our photos and music brings the available storage to 1.5GB.

Speed tips for slow iPhones continues on next page >>

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