iPhones and iPads have come a long way over the years, but one area they haven't improved as much as we might hope is in battery life.
Sure, the batteries are bigger, more powerful, more efficient, and charge faster, but the devices' power consumption has risen at the same time, so they don't last much longer than they used to.
The good news is, there's no shortage of portable power banks and battery packs to help make up for the shortfall. We've tested out a few, and here's our pick of the best.
If you're looking for a battery case for your iPhone, you can visit our round-up of the best here. iPhone X owners should also see our round up of the best battery cases for iPhone X over at our sister site Tech Advisor.
Moshi IonBank 3K
The Moshi IonBank 3K isn't cheap (£54.95 at Amazon UK but a slightly more affordable $34.99 in the US), but it's well worth the cash. Absolutely oozing with class, this premium-design power bank has a magnetic vegan leather case, flat, tangle-free Lightning and USB connectors built-in, and an aluminium front panel with a single LED built into the power button.
Rated at 3200mAh and running at around 65 percent efficiency rate, the Moshi will offer most standard iPhones a full charge. For the Plus models and iPhone X you're looking at more like 70- 80 percent charge, but even this is useful when you're out of battery and away from mains power.
The charging rate is fast, with the IonBank 3K building in a 2.1A output and 2.4A input. It supports passthrough charging, here known as SmartSense, which means you can charge both power bank and iPhone at once. Moreover, it supports synching when the USB port is plugged into a computer.
Read our full Moshi IonBank 3K review over on our sister site Tech Advisor.
EasyAcc 20000mAh Power Bank
EasyAcc once had the RRP on this bank at £59.99 on Amazon, but they are never sold for that much - the products are quality though, so don't think this is some knock off. They are excellent value, and this 20000mAh pack is no exception.
To put its power into perspective, EasyAcc claims this particular iPhone battery pack can, when fully juiced, charge an iPhone 7 six times. If you leave the house and you'll be away from a plug for a couple of days, it could be all you need. Plus, it's capable of charging up to four devices at once, and even comes with a little torch.
Techlink 13600mAh Powerbank
The Techlink 13600mAH is a powerful battery pack that can charge your iPhone up to 8.8 times. It has 2 USB ports, so you're free to charge your iPhone and an iPad at the same time if you wish. It comes with useful indicator lights that tell you when the power bank is low on charge as well.
The Techlink power bank is designed to prevent overheating, overloading, over-charging, and short circuiting and comes with a 2 year warranty.
JBL Charge 3
There are a few speakers around that will allow you to use their internal battery to top-up your iPhone every now and then, but JBL’s Charge 3 is a versatile, portable option that you can easily carry around when you’re travelling.
The Charge 3 is a small cylindrical speaker that's so it’s easy to slip into a backpack when you’re on the move. It works well as a portable speaker, with Bluetooth connectivity, and a bass radiator that gives it a nice, strong sound. There’s also a noise-cancelling microphone for taking phone calls too.
The rubber casing of the Charge 3 provides good protection for bumps and drops when you’re in the great outdoors. It’s even rated IPX7 for water-resistance, which means that it can cope with being submerged in up to 1m of water, so it’s a good choice if you’re out in bad weather or splashing around on a beach.
You can link multiple Charge speakers together to really pump up the volume, and there’s a Social mode that lets you pair it with up to three Bluetooth phones or tablets all at once so that your friends can join in and play their own music too.
Despite its compact size, the Charge 3 manages to squeeze in a powerful 6,000mAh rechargeable battery. That should last for up to 20 hours when just playing music, but it can also fully recharge most iPhones and still have enough juice left to keep playing music for a few hours too.
Nomad slim leather charging wallet
This neat little wallet from Nomad looks like a classic leather card holder, but there's a 2,400mAh battery in there with a small Lightning connector.
It's designed for any iPhone with Lightning (so iPhone 5 and later) but you could top up an iPad too. It charges via the supplied micro USB cable and holds 4 cards, plus has a little pocket for notes or coins.
We should clarify that it doesn't open up like a regular wallet, but it's still a smart way to carry your essentials and a charger.
This smart little cylinder packs a surprisingly large 3,550mAh in a body that's 102x23mm.
That capacity is more than most smartphones, meaning carrying this slim battery pack with you will give you the reassurance of a full recharge. Itself recharges via microUSB pretty quickly, and we've used it to fully charge several iPhones.
It is affordable too, compared to high street prices.
Anker Astro Power Bank E1 6700mAh
While we haven't personally tested this battery pack from Anker, it promises a powerful 6,700mAh, which is enough to charge an iPhone 7 or iPhone 6 twice, and an iPhone 7 Plus once. Anker prides itself on it being as small as a chocolate bar, which means it can fit easily in your pocket or bag. Plus, a durable exterior makes it drop proof.
To charge the Anker Astro itself takes 5.5 hours, which then charges connected devices at a 2A output. At £16.99/$19.99 you get an affordable power bank that comes with a travel pouch and an 18-month warranty.
Available in black, white, blue and red.
Mophie Power Reserve
Mophie's Power Reserve really is designed to be pocket-sized - in fact, it even comes with a keyring attachment so that you can keep it with you at all times.
The Power Reserve measures just 72mm long, 38mm wide and 14.5mm thick, so it's certainly easy to carry around if you do decide to keep in your pocket or in a bag. It's available in a number of different colours, and there's a quick-release button that lets you detach it from the keyring when you need to use it.
That compact design means that its battery capacity is relatively limited at 1350mAh, and Mophie says that it is primarily intended for use with the iPod or iPhone rather than larger devices such as an iPad. Even so, that should be enough to give you about 50% extra charge and keep you going for a few more hours.
There’s a Lightning cable that folds out from the side, but – apart from a USB connector to charge the battery itself – there are no other connectors, so you won’t be able to use it with older iPods and iPhones that use the original 30-pin connector.