Are you trying to find power bank for smart phones among various brands on the market but aren’t sure where to begin? To assist you in finding the right one, we’ve put together a list of the 7 best to help you pick the perfect one!
We investigated and evaluated a number of the top-selling power bank for smart phones on the market in order to create our list of the best. Making a decision among the many options available is never simple. There are an infinite number of models available, each with a distinct price. And as you’ll find out, the best options aren’t usually the ones you imagine! This comparison is rich and relevant because of the numerous factors that were employed. You will find products featured in this ranking not only based on their pricing but also on their features and other customers reviews. To write this review, we completed 27 hours of research and did 72 power bank for smart phones tests. You won’t need to pick products at random any more. If you’re unsure of what to look for, browse our list and consult the buying guide!
An overview of our top picks
Table of contents
The best power bank for smart phones you can buy today
- 【Small & Slim】2 Pack 10000mAh Power Bank using high-quality Li-polymer electric core and Ultra Slim Design, weighing just 181g and only 14mm thick. Grippy design is easy to hold, easy to toss into a bag and incredibly portable. Adopts our advanced intelligent controlling IC, higher quality, safer and more reliable, powerful and longer-lasting life after 100% checked and continuous aging test;
- 【Dual Output & Input】2 usb output ports, can fast charge 2 devices at the same time, The portable charger can fully refill the battery itself in 6-8 hours at 5V 2.1A and meet the charging needs of mobile phones, tablets and other electronic devices;
- 【Universal Compatibility】The power bank supports iwatch, Airpods, Samsung Galaxy, most other Smart cell phones, Tablets, Bluetooth devices and more. It can charge 6 to 8 times to eliminate the anxiety of your battery exhaustion. Suit for travel, and other indoor outdoor activities;
- 【4 LED Lights & Certified Safe 】 Four led lights show the current remaining power of the item(25%~50%~75%~100%), easily press the power button to turn it on or off. Built-in smart protection system, the USB battery pack ensures complete protection for you;
- 【24 Months Support Services 】AONIMI 10000mAh portable battery charger, Micro USB cables, user manuals. AND 24 month warranty policy and 24 hours friendly customer service. easy-to-reach support! Any question, please kindly contact us.
- The Portable Charger Power Bank compatible with iPhone 15/15 Plus/15 Pro/ 15 Pro Max /iPhone 14/ iPhone 14 Por Max/iPhone 14 mini / iPhone 13 Por Max/13 Mini/13/12/11/XR/11 max/XS Max/X; iPhone 8 Plus/8/7 Plus/7/6s Plus/6 Plus/6/SE/5S; Samsung Galaxy S23/S22S21/ 20/S10/S9/S8 /Note20,Note10,Note9, Galaxy Z Flip4, Galaxy Z Flip3,Galaxy Z Fold3, Galaxy A73 ,A13,A33,A53, A52,A42,A32; LG G8, LG G7, LG X4, LG Q60, LG K40, LG Q7; Google Pixel, Google Pixel XL, Google Pixel 2 etc
- Portable Charger with 5V 3.1A 2 USB Output ports ,which can fast charge 2 devices at the same time.You can share with your companions to get rid of worries about the battery life of your phone. The USB C and Micro USB input ports can fully refill the battery itself in 4-5 hrs at 5V 2.0A.
- Power Bank has 15000 mAh ultra-high capacity can give you an excellent battery life experience. Keep you without extra worry about low phone battery.
- Power bank bulit-in Intelliegent Controlling IC can automatically identify and is universally compatible with all products, It switches the corresponding current and voltage to charge the device. Also IC can convert fluctuating current into stable current, It can effectively prevent your power bank overcharge, overvoltage, overcurrent and short circuit.Bring you the safe using experience.
- Portable Chargers are very compact ,they are not only for portable charging but also around the home making it a favorite for travel.You could benefit from these battery packs When you go out.Allowing you charge mobile devices without having to be tethered to a plug socket. You could get more convenience and happiness from these high-quality power banks.
- Power bank uses the safe high-density lithium polymer battery module, which is more compact and has a larger battery capacity, It exceeds the traditional Lithium ion battery on safety.The safety of customers is most concerned about ,Customer satisfaction is our greatest motivation. We sincerely hope that this shopping experience will bring you good memory.
- Power bank has three built-in output lines, two of which are also input lines. Portable charger with built-in Micro, Type-C, IOS cable for output. It also has a micro/typr-C input port for charging this portable battery. Just carry this product and get rid of a bunch of complicated cables, allowing you to conveniently charge your phone anytime, anywhere. And can share to friends to charge together.
- Power bank has two 5V3.1A USB fast output ports, and built-in 10W wireless charging. Up to 3 devices can be charged at the same time. Can be shared with friends to charge together.
- Portable Charger has a built-in high-precision LED display, which allows you to accurately control the remaining power and is more convenient to use.
- Power bank have large battery capacity.We use A-grade quality high-density lithium polymer batteries. The 40000mAh battery capacity can meet the daily charging needs of a mobile phone device for a whole week.
- Portable Charger has a built-in new smart IC chip, which can accurately identify the vast majority of mobile devices on the market and automatically match the corresponding output power. The IC chip will also provide protection charging for the Power bank, intelligently monitor the voltage and current, and actively avoid a series of potential dangers such as overcharge, overdischarge, short circuit, and high temperature. It can escort your device during use.
- Portable Charger [15W Max Wireless Charging]: Wireless portable charger support 5W, 7.5W,10W and 15W Max wireless fast charging. Conveniently charge your wireless devices up to 15W without connect cable.
- 25W PD Fast Charging & QC 4.0 Fast Charing Output: portable charger with 25W power delivery 3.0 output and quick charge 4.0 output, combine to deliver an optimized charge to your devices at up to 25 W. Fast charging for cellphone up to 100% within 1.5 hours.USB-C fast charging cable and PD wall charger full charge this portable charger within 3.5 hours.
- Simultaneous Charging + Smart LED Indictators: Get a 15W wireless charge for your wireless cellphones while charging another device via one of two micro usb outport (QC 4.0 +2.1A) or usb-c 25W PD port. The LED battery level indicator show the remaining battery level.You will know when this power bank need be charged.
- High Capacity & Safe of Power Bank: 30,800mAh capacity can charge more than 8 times for iphone 14 and 6 times for iphone 14 pro max. power bank built-in intelligent chip can protect your devices against overcharge, overdischarge, excessive curretns , short circuits or overheating.
- What You Get: FOCHEW Wireless Portable Charger x 1, Micro USB Cable x1 (Not including USB C cable), User manual x1 . And 24 month warranty policy and 24 hours great customer service.
- Tips: This portable charger not sutiable for wireless charging of bluetooth headphones.
- 【No data cable required】The portable charger has 4 built-in data cables: 1*USB-A data cable, 1*Micro USB data cable, 1*LT data cable, 1*Type-C data cable. 2 output ports: 1 * Type-C port, 1 * Micro USB port. It can charge up to 5 devices. You can use this portable charger to charge your mobile phone anytime, anywhere, without the need to prepare a charging cable, which solves the problem of multi-wire entanglement.
- 【Super Mini】One of the smallest and lightest 12000mAh portable charger. You can put in your pocket, clutch bag or purse handbag easily.Compact design and rounded corners that make them comfortable in the pocket or in the hand.
- 【Intellgence LED display】The intellgence LED battery level indicator show you the remaining battery level.No more guessing whether need to charge it or not.
- 【Smart Security Protection】The mobile power bank has a built-in full smart chip security system and a UL-certified lithium-ion battery to provide security protection for you and your equipment. Support over power, over voltage, over charge, short circuit protection and automatic power off.
- 【Services and products you will get】12-month warranty, 24-hour online after-sales service, and friendly replacement policy. Any related issues are covered by a friendly replacement or money-back guarantee, and 24-hour online after-sales service is supported. Product list: 1*12000mAh mobile power bank, 1*Type-C cable, 1* lanyard, 1* user manual.
- [International Compatibility]: 5 in 1 International Power Adapter with 4 x USB ports and 1 Universal AC Socket, enough to simultaneously charge 5 devices. The travel adapter Covers over 150 countries like USA,Canada, Mexico,Germany,Japan,China,Korea,Brazil, Europe, Asia, the Middle East, Etc.
- [Versatile Plug Options]: Whether it’s the wall plug you need, or the integrated USB slots, all is ready for you to go! It is compatible for iPhone14/13/12 X/8/7/6S/5S/4S, Samsung Galaxy S7/S6/S5/S4, Sony, Nokia, LG, Tablets, laptop, Bluetooth Speaker, power bank, digital cameras and almost all USB devices.
- [Built-in Smart IC Chip]: SAUNORCH Universal Power Adapter built in Smart IC Chip, intelligently recognizes your devices, adjusting the right current output automatically, boosts its charging speed, allow simultaneous charging your devices at high speed.
- [MultiProtect Safety System]: As a Global Universal Travel Adapter, Qualified with FCC CE and RoHS Certified safety system, made from durable fireproof material, built-in 8.0 Amp fuse and safety shutter design, ensures complete protection for you and your devices.( Note: input voltage 100V - 250V,880 Watt. max. at 110V, 1760 Watt. max. at 220V, 2000 Watt. max. at 250V, Do not exceed the Power limit.)
- [Worry Free After Sales Service]: If you have any question about the product, please feel free to contact us, we offer full 24/7 courteous friendly customer service for all of your needs.
- [Built-in AC Wall Plug And Cables] The 90-degree folding design saves storage space and allows you to take it out at any time. Not only does the wall charger power bank have built-in micro, USB C, and other cable for iPhone, but it also has a USB input & output port, and a USB C input port, which can meet the needs of daily charging. When you travel, carry it with you and never worry about forgetting to bring the charging cable.
- [Up to 22.5W QC Fast Charging] The USB port of the portable power bank supports up to 22.5W fast charging output, which can quickly charge your device and save charging time for you. It can charge up to 3 devices at the same time. Equipped with an intelligent LED display, you can always know the remaining charge level of the portable power bank.
- [Two Way To Recharge The Power Bank] One is charging the power bank through the AC wall plug, it will be fully charged within 11 hours. The other is using the 9V/2A charging cable to charge the portable charger itself, it will be fully charged within 6 hours.
- [20000mAh Capicity& Wide Compatibility] Product dimension is 5.91 x 2.83 x 1.09 in,weighing has 0.81 lb. The high capacity of 20000mAh provides several charges for your device, depending on the capacity of your device. It's compatible with most of smart devices(Such as compatible with iPhone/Samsung/Android/Tablets etc)
- [Safety and Reliable] The smart chip can protect your device from overcharge protection, overvoltage protection, overcurrent protection, short-circuit protection, and overtemperature protection, creating a safe charging environment for you.
- New Design Portable Charger with 26800mAh Ultra-Huge Capacity, adopts our advanced intelligent controlling IC, higher quality, safer and more reliable, powerful and longer-lasting life after 100% checked and continuous aging test;
- Universal Compatibility: The power bank compatible with iPhone, iwatch, Airpods, Samsung Galaxy, most other Smart cell phones, Tablets, Bluetooth devices and more. It can charge 6 to 8 times to eliminate the anxiety of your battery exhaustion. Suit for travel, and other indoor outdoor activities;
- Super Fast Charging: Portable charger power bank high capacity 26800mAh could charge your phone at least 5-7 times, suitable for business, travel, going out, you don't have to worry about your phone low battery.
- Charge 3 Devices: Power bank with 3 Output Ports, QC3.0 output, PD output, 2.1A USB output.You can charge 3 devices simultaneously. Power Delivery 3.0 output and Quick Charge 3.0 output combine to deliver an optimized charge to your devices at up to 20W.
- 24 Months Support Services -- Ekrist 26800mAh portable battery charger, Micro USB cables, user manuals. Together 2 Years friendly, easy-to-reach support! Any question, please kindly contact us.
- Portable Power Bank Compatible for Nintendo Switch takes no disturbance during gaming and lightweight design allows to easily travel. Built-in Type-C cable and Type-C port provide high-speed charging and recharging simultaneously.
- The detachable back installation design allows you to easily slide to disassemble or lock for charging. A 10,000 MAH high-capacity switch battery box can extend 10 hours of game time.
- The Compact Travel Backup Battery Pack for Nintendo Switch supports maximum 5V/3A charging current to all smartphones and tablets.
- The Rechargeable Extended Battery Charger Case has smart plug-in and plug-out identification, current line compensation and up to 92% conversion efficiency. Smart recharging current adjustment to work with all types of charging adapters.
- Enclusive multiprotect technology ensure total protection for you and your devices. Against short circuit, over-voltage, over-current, over-charge and high temperature. You can feel free to play Nintendo switch games while charging.
- Andrei, Peter (Author)
- English (Publication Language)
- 289 Pages - 05/29/2020 (Publication Date) - Independently published (Publisher)
- Amazon Kindle Edition
- Amador, Richard (Author)
- English (Publication Language)
- 400 Pages - 01/04/2019 (Publication Date) - Inktelligence (Publisher)
![VRURC Portable Charger Built-in Cables and AC Wall Plug, USB C Power Bank 10000mAh, [2023 Upgraded Version] Phone Charger Compact Lightweight External Battery Pack for Smart Phones, Tablets etc-Black](https://m.media-amazon.com/images/I/41bGxGCReML.jpg "The 8 Best power bank for smart phones of %currentyear% 39")
- [Portable Charger With Built-in Cables & AC Wall Plug] Not only it has a built-in Micro cable, USB C cable, and other charging cable for iPhone, but also is equipped with a USB port,and USB C port. Also, Portable phone charger is built-in wall plug that charges the power bank itself directly from the wall outlet.
- [Slim & Compact Design] Product dimension is 5.9 x 2.8 x 0.7 in,weighing 8 Oz. Compact design is more convenient for us to carry on the go, and does not add any weight.
- [Smart Digital LED Display] You can know the remaining power at a glance via LED Display. Also, the 3D texture on the surface provides you with a better 3D touch and grip to prevent the power bank and phone from slipping off.
- [Wide Compatibility] Using the built-in charging cables to charge, the portable battery charger is compatible with iPhone, Android devices, and USB-C most mobile phones and smart devices etc. This external battery power bank can meet most of the charging needs of daily life.
- [PRODUCT PACKAGE] 1x Power Bank, 1x User Manual.
- Get real-time doorbell and motion alerts on your smartphone or tablet
- See and speak with visitors with HD Video and Two-Way Talk
- Arm and disarm your Ring system
- Dutch (Publication Language)
- A TRAVELER'S BEST FRIEND Don’t travel with the stress of your phone dying or scrambling to find an outlet at an airport. The "Adventure Port" includes an ultra slim and lightweight 5000mAh power bank hidden inside a sleeve ready for use at any moment. When you are on the go and your phone battery is running low just plug it into your power bank located inside your passport holder for a complete charge. Once you get to your destination, recharge your power bank for your next journey!
- Amazon Prime Video (Video on Demand)
- Rashida Jones, Ben Mendelsohn, Reba McEntire (Actors)
- Troy Quane (Director) - Brad Copeland (Writer) - Michael J. Tavers (Producer)
- English (Playback Languages)
- English (Subtitle)
- Audience Rating: PG (Parental Guidance Suggested)
- 【Portable Charger with Built-in Cables】Power bank with built in 3 charging cables and 1 recharging cable, USB-C cable, for iPhone cable and Micro cable for output, you can use this three cable direct charging for your different devices, also built-in USB-A cable for recharging, perfect battery pack for travel, no need to carry any extra cords.
- 【Upgrade USB C Input & Output Port】Portable phone charger with usb c in & output port, suitable for your iPhone, iPad, Samsung etc USB C series devices, giving you more charging optiones, unlike most chargers featuring a USB C input port only. with the cable and ports total 5 outputs, support charging for 5 devices simultaneously.
- 【Compact Design & Portable Size】This slim portable charger only 5.7 x 2.7 x 0.73 inches, weight 9.17Oz, with 10000mah powerful capacity, you can enjoy your trip whole day. also built in multi function micro cable as lanyard for easy to carry and prevent falling.
- 【Two Ways for Recharge Power Bank】Built-in usb-a cable for recharging directly, or charging power bank through the usb c port, both ways full charger only needs 6 hours. portable charger with LED display, you can know the accurate remaining battery percentage.
- 【Intelligent Safety Charging】Phone battery power bank with high quality smart chip to prevent over-charge, over-voltage, over-current, and short circuit for your devices.【What You Get】1x 10000mah power bank, 1x Travel bag,1x Manual,24 hours friendly customer service.
![Malwarebytes Premium Software | 5 Device 1 Year (PC, Mac, Android) [software_key_card]](https://m.media-amazon.com/images/I/41jqSc7IKsL.jpg "The 8 Best power bank for smart phones of %currentyear% 44")
- PROTECTS YOUR DEVICES ON MULTIPLE PLATFORMS: Compatible with Windows, Mac, Android devices.
- UNMATCHED THREAT DETECTION: We found malware on 29 percent of devices that already had a third-party antivirus installed. That’s the power of our innovative technology. We block sophisticated cyberthreats that other programs miss, providing an effective way to secure your devices and data.
- INCREDIBLY EASY TO USE: Our simple user interface enables you to fully control your protection to meet your needs without requiring technical expertise. You can schedule scans, adjust protection layers, and choose your desired scan mode. Protecting your devices shouldn’t be complicated.
- ADVANCED MALWARE, RANSOMWARE PROTECTION: Helps protect you from websites that download ransomware, steal login credentials, or run scams. Reduces your exposure to hackers and cyberthreats while protecting your devices and data.
- PROACTIVE EXPLOIT, AND VIRUS PROTECTION: Protection from the financial and reputational risk posed by a ransomware attack. Shields your device and data from vulnerable and unpatched software until it can be updated. Malwarebytes finds more threats compared to traditional antivirus programs so you can restore your device quickly to its pre-infection state.
- 🔋 SEVEN IN ONE:ANOUV portable charger with built-in USB C & micro and other three cables are compatible with Apple, Android, Type-C and all smart devices.LCD display shows the remaining battery visually,The built-in AC Wall plug allows you to recharge directly from the wall outlet,Worry-free to forget carrying any extra wall charger and cables,enjoy your travel!
- 🔋 PD 22.5W FAST CHARGING&FOR MULTIPLE DEVICES:Our power bank up to 22.5W fast charging,this portable phone charger with with 5 outputs,3 Cables outputs charging and additional USB C and USB A outputs,It supports 5 devices charging max simultaneously.Two Ways Quick Recharge,Portable charger with wall plug&Type-C Quick full recharge.
- 🔋ULTRA SLIM&BIG CAPACITY: The slim battery pack charger portable has a compact only 5.76 inch * 2.72 inch * 0.68 inch,and 230g weigh,10000mAh big caacity,it can be easily put in your pocket or travel bag and suitable for airplane travel or outdoor activity that brings you the best experience on the go.
- 🔋WIDE COMPATIBLE : perfect portable phone charger compatible with iPhone 15 Pro Max，15 Pro, 15，14 Pro Max, 14 Pro, 14, 13 Pro, 13, 12 Pro, 12, 11 Pro Max, 11 Pro, 11, XS Max, XS, X, XR, SE,iPad Pro 2021/2020, And it with type-C cord for Android compatible with Samsung S23, S22, S20, Note 20,Google Pixel, tablets.Battery pack support low-current Charging can also work with smaller devices like Bluetooth headphones, AirPods, fitness trackers, smart watches, etc
- 🔋EXCELLENT SERVICE - You can get 2x 10000mAh power bank（Black+White）,1x Manual. If you have any problem, free to contact us. We will solve your problem within 24 hours.
![VRURC Portable Charger Built-in Cables and AC Wall Plug, USB C Power Bank 10000mAh, [2023 Upgraded Version] Phone Charger Compact Lightweight External Battery Pack for Smart Phones, Tablets etc-Green](https://m.media-amazon.com/images/I/31IbBkBWo1L.jpg "The 8 Best power bank for smart phones of %currentyear% 46")
- [Portable Charger With Built-in Cables & AC Wall Plug] Not only it has a built-in Micro cable, USB C cable, and other charging cable for iPhone, but also is equipped with a USB port,and USB C port. Also, Portable phone charger is built-in wall plug that charges the power bank itself directly from the wall outlet.
- [Slim & Compact Design] Product dimension is 5.9 x 2.8 x 0.7 in,weighing 8 Oz. Compact design is more convenient for us to carry on the go, and does not add any weight.
- [Smart Digital LED Display] You can know the remaining power at a glance via LED Display. Also, the 3D texture on the surface provides you with a better 3D touch and grip to prevent the power bank and phone from slipping off.
- [Wide Compatibility] Using the built-in charging cables to charge, the portable battery charger is compatible with iPhone, Android devices, and USB-C most mobile phones and smart devices etc. This external battery power bank can meet most of the charging needs of daily life.
- [PRODUCT PACKAGE] 1x Power Bank, 1x User Manual.
How to choose a good power bank for smart phones
Does the idea of finding a fantastic power bank for smart phones make you anxious? When it comes to purchasing this product, specifically when deciding which model to select, has your head been spinning between options? You are not alone if that is the case. We are aware of the pressure involved in the purchasing process!
Your presence here indicates that you are interested in power bank for smart phones. Before choosing which product would be the best for your needs after being inundated with information, locate a reliable source with genuine selections. You can get that information from a variety of sources, including buying guides and rating websites, word-of-mouth recommendations from friends and family, online discussion forums where users can share their own experiences, product reviews that can be found all over the internet, and YouTube channels. You can only get the right product through exhaustive analysis. But you realize that’s not always simple. In order to ease your concerns, we have taken the time to develop a list of the top power bank for smart phones products available right now. You might be wondering how we came up with the list. How was this buying guide developed?
First, we used our algorithms to gather as much reliable data as we could about these products. To verify all the data gathered, we used both artificial intelligence and a lot of algorithms.
Then, our experts used criteria that are recognized in the business to evaluate them according to their quality to price ratio, allowing us to choose the top power bank for smart phones on the market right now!
The selection of the goods is not arbitrary. Before creating a list, we take into account a number of factors. Below are some of the criteria discussed:
Brand Value: What happens if you choose a dubious brand just because it appears to be a good deal? So the likelihood of receiving a product with a short shelf life increases. That is due to the fact that well-known brands have a reputation to uphold, while others do not. Top power bank for smart phones brands strive to provide some distinctive traits that set them apart from the competition. So, hopefully one or more of the items on our list will be perfect for you.
Features: Useful features are all you need, not tons of them. We consider the important aspects and select the top power bank for smart phones based on those.
Specifications: Numbers always help you measure the quality of a product in a quantitative way. We try to find products with higher specifications, but with the right balance.
Quality: A product’s quality may always be quantified with the aid of numbers. We look for goods with better standards that strike the proper balance. The best quality product that gets highly appreciated and recommended by experienced users.
Customer ratings: Would it be accurate to suggest that the power bank for smart phones were used by hundreds of customers before you? Superior ratings indicate that many customers had better service.
Customer Reviews: Like ratings, provide you with accurate and reliable information about the product from genuine customers. Customer ratings are very important to all of us because they contain accurate and reliable information about the customer service we received from several hundred customers.
Seller Rank: This is very intriguing! Not only do you need a good power bank for smart phones, you also need a product with rising sales that is trendy. It accomplishes two goals. First, the expanding user base proves the quality of the product. Second, given that number, producers must be able to offer greater quality and after-sales support.
Value: You get what you pay for, they say, so consider the value. Cheap isn’t always good and expensive isn’t always bad. However, that does not imply that spending a lot of money on a product that is flashy but underwhelming is a good idea. Before adding them to the list, we make an effort to evaluate how much value you can get for your money from your power bank for smart phones.
Durability: Durability and reliability are closely related concepts. You will benefit from a strong and long-lasting power bank for smart phones for months and years to come.
Product availability: Products come and go, and new ones replace the old ones. Most likely, a few new features and required changes were made. What use is it to use a supposedly good product if the maker no longer supports it? We make an effort to highlight products that are current and offered by one or more trustworthy sellers, if not more.
Negative Reviews: Yes, we do take that into account as well! The goods with the majority of bad reviews are filtered out and disregarded when we choose the best-rated one on the market.
These are the standards by which we selected our power bank for smart phones. Do we end our process there? Hell no. The most crucial fact about us that you should be aware of is that we regularly update our website with current and pertinent information. We have one more layer of filtration since we place the greatest importance on reader satisfaction. Please let us know if any product included here is incorrect, irrelevant, subpar, or simply out of date. We always value your opinions, and we’ll work hard to make any necessary corrections to our list in response to them.
Why should you believe us?
There are now thousands of possibilities for these products on Amazon, but choosing the best one can be difficult and time-consuming. And what power bank for smart phones should you purchase in 2022?
This guide is the result of more than 10 years of experience in researching, testing and writing about many topics. Each member of our team is an authority in their area. We read every article we could find online and every consumer review on every retail website for seven hours. Additionally, we discovered a ton of websites that offered helpful resources, including buying tips and thorough information on power bank for smart phones.
