Mobile

Is this the end of your ‘dead cellphone’?

Will the words "my phone died" soon become extinct?

A number of start-ups are creating portable phone rechargers in the hope that those stranded moments will become a thing of the past.

And even though battery life is getting longer—witness the release of the iPhone 6—our increased usage puts more demand on our devices.

Combine longer hours, more applications, faster microprocessors and bigger and generally brighter screens, and the need for battery capacity becomes bigger than ever. "Battery life continues to be an issue, as people shift even more of their computing minutes to smartphones," said J.P. Gownder, vice president and principal analyst at Forrester Research.

"We're not only using them for communications (email, social media) but also for commerce (researching goods, purchasing goods), media (video consumption, reading)," said Gownder. "And, soon, perhaps paying for goods and services (Apple Pay)."

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Here are four gadgets designed to address the need.

QBracelet
Source: QBracelet

QBracelet is a unisex, lightweight bracelet that's virtually impossible to tell that it also doubles as a charger. The freestanding fashion wearable is manufactured for both Apple and Android devices and comes in multiple colors and sizes.

Cobra Jum Pack
Source: Cobra

The Cobra JumPack is a portable pack that allows you to charge your mobile device and even jump start your car. The device also has a built-in LED flashlight with a strobe and S.O.S. function in case of emergencies.

Powerslayer
Source: Powerslayer

Powerslayer, made by Velvetwire, is a USB charger that claims to have the most efficient way to charge a mobile device, which would eliminate energy waste, while also improving the lifetime of a battery's performance.

Ventev charging device
Source: Ventev

Ventev makes a variety of portable products for charging, including a gadget that serves both as a protective case and built-in battery backup charger.

Many of the companies origins have a similar back story. The founder of QBracelet, for instance became stranded whiletrying to meet with a friend in Italy, but had a dead phone. And the founders of Velvetwire, a married couple, were out at sea for two years and learned the importance of conserving energy.

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Forrester's Gownder believes this space will grow as long as phone usage continues to increase.

"Given the centrality of phones to our lives, the future for external charging devices as a backup is bright."