Typical mobile users check their phones about 110 times a day, so it\'s no surprise that most smartphone batteries are dead before the end of the day. Running out of power can be a real nightmare when it\'s not possible to reach the power outlet. That\'s why portable battery packs are essential gadgets for anyone who is worried about running out of juice while running around. They sound like: a backup power supply you charge at home and then power your phone on the go. What to look for is to be sure that additional charging power is needed, here is what to look. Size and weight while the extra power boost is welcome, it is not welcome to carry a bulky battery pack with you throughout the day. The height of most units is around 6 inch, and larger units usually provide better charging. The charging time should have at least one indicator that will let you know once the device is fully charged, but ideally there will also be a monitor that accurately shows how much power it has left. Most importantly, the battery pack should do the work at hand. When you need it the most, it needs to keep the charging time long enough to give you emergency power. Find a pack of lithium-ion battery. Like most smartphones, smaller devices should be able to charge twice from a fully charged battery pack; Larger, like the iPad, should be able to go from backup source to at least 50%, from 0%. In some cases, the battery pack has multiple charging options that can be multiple USB ports or a combination of USB and 2. 1 Amp ports. This does not necessarily mean that multiple devices can be charged at any time, but it would be better if the packaging does support simultaneous charging. Compatibility some portable chargers are designed specifically for a device like the iPhone, while others are compatible with a variety of gadgets from smartphones to cameras. If the package does support many different devices, it may have different charging times and charge depending on the gadget, so be careful. With this in mind, here are our top five charging packs. 1. TeckNet power supply group 15000 mAh USB external backup battery pack size: 14x5. 8 x 2. 2 cm Weight: 290g Battery capacity: 1500 mAh TeckNet Power Bank is the number one TeckNet Power Bank with a charging efficiency of 89%. The company says it can charge the iPad 3 or iPad 4 more than once, while smartphones can charge more than eight times. It has super fast charging output so your phone can recover to full power at any time. With a dual USB port, it is also possible to charge both devices at the same time, but keep in mind that this will run out of the packaged power supply faster. The TeckNet Power Bank is light weight, large capacity and compatible with all USB devices, and is a great all-in-onerounder. 2. Anker Astro Portable 15000 mAh Portable power supply group this Anker Astro E5 is the latest product in the Anker battery pack series. Its 15000 mAh capacity is large, and the charging output is fast. it is an ideal choice for people who often go out. It charges almost seven times the iPhone, four times the Galaxy S4, and almost all the iPad. Its high density battery also means that it can provide power while keeping it compact. Again, it provides simultaneous charging thanks to the dual USB port. One of the more unique features is the built-in torch, which may come in handy. 3. EasyAcc 12000 mAh Power Pack 4 USB 3. 5A output portable charger easy Acc power pack capacity drops but it has to make up elsewhere as it is also able to charge the iPhone six or seven times. It is compatible with almost all mobile devices, including smartphones, tablets, ipod and Bluetooth speakers, and has four USB ports to charge up to four smartphones or two tablets at the same time. The device is also equipped with microchips that prevent short circuits, so your technology is always safe and reliable. However, the downside is that it is slightly larger and heavier than most other battery packs in this list. 4. The PowerGen 12000 external battery pack is found on Amazon. Size: 9. 7 x 2. 3 x 8. 4 cm Weight: 345g Battery capacity: 1200 mAh, the price is so reasonable, it\'s hard to complain about anything PowerGen offers. It has a high capacity of 12000 mAh and can provide 70 hours of talk time and 35 hours of video playback for the iPhone 4. Again, it\'s a lot heavier than a competitor, but it has three USB ports that allow you to charge three devices at a time. Compatible with all major smartphones, including iPhone 5, HTC One X, Samsung Galaxy S3, and other devices such as tablets, ipad and Kindle Fire, for those with all sorts of gadgets, this is the ideal choice. 5. PNY T2600 portable USB battery charger this battery pack is the least powerful of our top five, but it doesn\'t have juice and it definitely makes up for that in terms of portability and style. This is a very stylish device with a USB port that can charge any smartphone on the go. The PNY T2600 has a 2600 battery which is a small part of the other four batteries in the list, so it only lasts for two hours, but if it is only used in an emergency, it may prove sufficient, not a regular source of power.