Many iPhone and Android smartphone users want to boost battery life but adding a special battery case adds bulk and weight to your super-slim Apple or Android smartphone, and non-case battery packs require you to lug a tangly cable round with you too. Also see: 9 best portable USB chargers 2014
We’ve tested and reviewed battery cases from the likes of Mophie and Powerskin. Read our Mophie Juice Pack Helium review, Mophie Juice Pack Air review, and PowerSkin battery Case for iPhone 5 review. See also Best battery case for iPhone 5, 5c and 5s.
Each of the above performed well and offer added protection for your valuable smartphone. But many will be put off by the extra bulk each case adds to your iPhone 5 or Android smartphone.
These work fine and pack a powerful recharging punch. The £80 Mophie Powerstation Duo boasts a whopping 6,000mAh charge – although it’s not too heavy, it is obviously larger than the less-powerful packs – except for the £90, 4,000mAh Powerstation Pro that is super-ruggedised for extreme sports or extremely clumsy people.
These portable battery chargers work with most smartphones and tablets as they have USB slots into which you connect your device’s charging cable. That means you need to carry round not just the battery pack but the relevant charge cable as well. And anyone who's reached into a bag for a cable knows they get tangled up almost immediately.
For an iPhone 5, 5c or 5s that might mean buying another £15 Lightning to USB cable, and Android smartphone users will need to pack a Micro USB cable. And if you forget either cable you can also forget getting that much-needed power from the battery pack to the dying phone.
The Phonesuit Flex XT micro battery pack beats the Mophie Powerstations by having a built-in Lightning or Micro USB connector, so no need to carry round a cable too.
iPhone 5/5c/5s users need the Flex XT with the Lightning connector. The Flex XT for Android has integrated Micro USB connector tip can power virtually any Samsung, HTC, LG, Google, etc, smartphone.
It also means you don’t have to take the phone out of a case just to sync it. The Phonesuit Flex takes up the Lightning or Micro USB port only when you need it. The company has recently updated the Flex to the Flex XT, with a longer Lightning or Micro USB connector to make sure it fits even more phone cases. It won't fit giant cases such as those from Otterbox but it should fit most others.
Above you can see the Flex XT working with an iPhone in a separate case.
The Phonesuit Flex XT offers a powerful 2,600mAh charge, which is significantly higher than the Juice Pack and PowerSkin battery cases. Four LED lights show you the amount of charge left in the Flex. You re-charge the Flex via the supplied Micro USB cable.
You simply connect the Flex XT to your phone to start charging. The phone should be fully charged in about two hours, says Phonesuit, but we had a dead iPhone back to a full charge in just over an hour. Once connected to the Flex a phone should be operational again within minutes if not immediately.
Phonesuit claims this will give you an extra 150% charge on an iPhone 5, and at least 100% to most Android phones.
Our tests confirmed that the Flex micro battery pack will fully recharge a drained iPhone, and then give up an extra surge – around 25% – when that charge is used up.
Phonesuit describes the aluminium Flex Charger as “thumb sized”. That’s a pretty fat thumb but it’s certainly equal to the length of an adult man’s thumb, and smaller than most battery packs.
It weighs 79g, which is around the same weight as the smartphone battery cases listed above.
You wouldn’t want it on your person all the time but it’s perfect for slipping into your bag when travelling. You won’t notice it’s there until you get that low battery warning.
The Phonesuit Flex XT Charger is available in three colours: Black Metallic, Red Metallic and Blue metallic.
If you buy direct from Phonesuit it costs $69.95 (about £45) which is reasonable. Shipping to the UK, however, is expensive, adding another $37 to the price to make a total of $107 (about £62). The Mophie Powerstation Mini (2,500mAh) requires a £15 cable but costs £50 including shipping. At £60 the Phonesuit Flex is reasonably priced but with cheaper shipping costs (Sena, for example, ships cases to the UK for $9.99) would be more compelling.
Thankfully you can buy the Flex XT from Amazon for £59.95 for the iPhone 5/5c/5s version, and just £49.95 for the Android version.