Whether you're planning to go down to the park for a picnic with friends and family, or are having some people round for a barbecue, it's nice to add to the ambiance with a bit of background music.
We've picked five portable sound systems and put them through their paces to see which makes the best outdoor companion. They're all battery powered and are designed to be portable, so many come with a carry case, strap or handle.
But each has its own strengths that may make it perfect for you, so just because we pick a single winner, don't simply ignore the others - we've chosen these five in particular from a long list of possible contenders, so they're all worth your consideration.
Battery-powered docks aren't your only option, of course. You can get speakers that draw their power from your iOS device, such as the £25 Griffin Travel Speaker.
Then there are several passive iPhone holders available, which boost the sound coming from its built-in speaker without the need for batteries. However, passive amplifiers have the disadvantage that the sound they're boosting isn't great in the first place - not a patch on the audio you'll get from a proper speaker dock like these. Oh, and if the great British weather doesn't hold for you, none of these are waterproof…
Altec Lansing Orbit MP3 IM227 - £25
Gear4 Explorer-SP - £50
Logitech Pure-Fi Anywhere 2 - £80
Logitech S715i - £95
Sony RDP-X80iP - £120
The five on test are all battery powered, four from internal cells you charge from the mains, the last on three AAAs. This, along with the fact that we've chosen them with portability in mind, means you can easily take them out of the house and power up your tunes.
Portable iPhone speakers tested
Test one: Sound quality
While it's important that these speakers are easy to carry around, you don't want something that makes your music sound rubbish. The good news is that none of these five commits crimes against music. But the old adage of getting what you pay for rings true, with the costlier speakers pushing out the best sound.
At the top end of our price range, the Sony is our joint favourite for the audio it produces. The bass really complements the crisp mid and high ranges, giving a depth to your songs without overpowering things.
Better still, there's a built-in equaliser with five presets you can use to tweak the sound, and it'll go plenty loud enough to provide the soundtrack to your picnic or garden party.
If you're not keen on shelling out £120 for the Sony, you can come down the price scale here without sacrificing too much in the way of sound quality. The cheaper Logitech S715i is equally impressive, providing a detailed overall picture with nicely defined bass plus clarity at the higher end.
Pushing up the volume isn't a problem for it, either. There's no built-in EQ, but don't forget you can still use your iPhone or iPod's presets.
Coming down to the cheaper of the two Logitechs, the sound does take a knock, the treble being noticeably muddier in comparison to the S715i, though the bass remains well-defined.
So for the £80 price tag, you're still getting a very good sound system - remember you're not going to be listening to both in quick succession like we have, which serves to highlight such differences. It's got a 3D sound option too, which does a reasonably good job of giving the audio more depth, at the cost of some clarity. And like the Sony and Logitech S715i, it's plenty loud enough.
Likewise, the Gear4's got the power to go nice and loud, though we noticed that the bass did start to distort as you got the higher volumes. At normal listening levels, however, the overall picture is nicely balanced. We found it was improved by switching on the 3D setting, which helps pick out the treble a bit better.
And finally we come to the little Altec Lansing Orbit speaker. We have to admit that we thought long and hard about whether it was fair to include such a dramatically different product alongside some of these audio heavyweights, but as soon as we heard it, we knew it deserved its place in this group test.
Okay, something this small is never going to be able to go all that loud (though you'd be surprised by how much noise it can produce), and you aren't going to get any real bass of note, but the overall picture you get is far more detailed than we'd expected from such a small speaker, and spoken word is clean and crisp, making this a great choice if you want to listen to a sports match while you're in the park.
Test two: Portability
Three things matter here: size, weight and robustness. The smaller and lighter the dock is, the less of a pain it's going to be to lug around the place.
The Sony is both big and heavy - far from ideal for taking to the park or beach, but fine for in the garden. Ditto the Logitech S715i.
The Logitech Pure-Fi Anywhere 2 and Gear4 strike a good balance between size and weight, but the Logitech wins.
Without question, the most portable here is the Altec Lansing, though we were concerned the cable grip could damage the wire over time and that the power switch could get pressed in your bag rather too easily. The plastic grilles behind the Gear4's material mesh feel a bit flimsy - not a dealbreaker, but less robust than all the others.
Test three: Extra features
Because these speaker docks are all portable, they come with helpful extras to aid you when taking them out and about.
When you buy the Gear4 or either Logitech model, you get a soft carry pouch in the box, which protects the dock to a certain extent when you're flinging it carelessly into your bag as you're rushing out the door. They're simple, and reasonably effective at protecting the dock from scrapes, but don't have carry handles to speak of.
One nice touch of the Pure-Fi Anywhere 2 is that its power adapter is designed to fit in the docking bay inside the pouch while you're transporting it. The tiny Altec Lansing doesn't bother with a case and makes do with just a wrist strap for carrying it, while Sony has gone for a grip handle cutout in the back of the dock, making it easy to pick up quickly.
All bar the Altec Lansing have some form of on-board controls, from the Logitech S715i's basic volume buttons to the Sony's more sophisticated touch controls for your music. To complement these buttons, all except the Altec Lansing have remote controls.
You might wonder why you'd want to take a remote on a picnic to zap a dock that's only a few feet away from you, but they do give more control options than what's on the docks themselves. They're also good when you're having a barbecue, so that you can skip songs playing through your device on the terrace when you're cooking down the bottom of the garden.
And don't forget that these speakers aren't just for use outdoors - when you bring them inside, the remote's a nice addition if you don't want to get up from the sofa.
Lastly, none of these speakers are limited to iOS devices either. All have standard 3.5mm aux-in capability so you can plug in other phones or MP3 players, though in most cases you'll need your own cabling.
And the best portable iPhone speakers are...
Gear4 Explorer-SP - £50
As we said right at the start, these five docks all have their strengths and are worthy of your consideration. Which you decide to spend your money on has to depend on where you plan to use it.
If you're just after something you can fling in a bag and take with you everywhere so that you can enjoy your tunes whenever you fancy, look no further than the Altec Lansing. It won't weigh you down or take up much room in your bag, and because it's so cheap, you'll likely be less worried about it getting damaged or stolen.
But sound-wise, we wanted more than you can get from such a small box. On that front, there's little to choose between the Sony and the Logitech S715i, both of which do a sterling job. But equally, we mustn't forget we're testing picnic speakers, which can't be too heavy, given all the other paraphernalia you're likely to want to take along with you. The Logitech S715i and the Sony are too heavy for us to recommend as true picnic speakers.
However, for something around the house, we can't recommend either of these highly enough. In fact, the S715i is now in our Tap! Top 10 list of accessories for your device.
And so we're left with the cheaper (and, crucially, lighter) of the two Logitechs and the even cheaper, if slightly heavier, Gear4. On a pure audio basis, we felt the Logitech Pure-Fi Anywhere 2 picked out the bass better, but then we loved the crispness of the treble coming from the Gear4, especially in 3D mode.
Not a great deal to choose between them there, then. But because these speakers are going to be taken out and about, you don't want one that's so expensive you're going to be worrying about it constantly.
Ultimately, then, for summer picnics and barbeques, the Gear4 balances portability, sound quality and price.