Anker Astro Slim2
|Image Credit: Anker|
The 4-light LED column indicates the remaining power available taking the guesswork out of knowing if there's enough to fully charge your smartphone. A built-in micro USB cord connects to Android devices while the USB port can be used for Apple device cables or the one that came with your phone. Both provide 1A of power to charge phones relatively quickly. The Astro Slim2 is compatible with all Android and Apple smartphones and tablets. It can also be used with 5V input USB-charged devices like bike lights, GPS unints and GoPro cameras.
The only negative aspect I could find about the Anker Astro Slim2 was in using the built-in micro USB cord with my phone in an Otterbox Defender Series case. This cord will not fit into the micro USB port on phones that have bulky cases or bumpers, but without these it works fine. To charge my phone's battery on rides I will put the Anker Astro Slim2 either in my Detours Slice top-tube frame pack or slip it behind my phone in my stem mount phone case. When my battery is running low, I simply plug it in and continue on my way without the worry of losing my data or navigation display.
The Anker Astro Slim2 External Battery is available on Amazon.
Tigra BikeCHARGE Power Pack
Next is the Tigra BikeCHARGE Power Pack from Bike2Power. Its silicone-covered weatherproof design protects it from drops, impacts and adverse conditions. A rotating mounting bracket holds it securely in place and can be attached to any tube from 18-40mm diameter in seconds. With a 2600 mAh Li-Ion battery, this compact unit will provide enough juice to charge most smartphones at least once. It has charged my Android phone's nearly dead battery to 100% pretty quickly but was fully depleted after doing so. iPhone users may have a little more juice remaining for a partial second charge. Either way, it will double the use time of your smartphone.
Out of the packaging it comes with the battery pack, USB to micro USB cable, rotating mounting bracket and four silicone caps. These caps expose only the ports needed (USB, micro USB, dual and closed) and protect them against rain, snow, dust, and dirt.
I have tested it out on bumpy gravel roads and even bumpier dirt singletrack with the mount holding secure and not moving or rotating. For mountain bikes with larger frame tubing diameters, the mounting strap will not be long enough to work. Because of this, I placed it in an out-of-the way spot on my seat post. Stem or handlebars are other mounting options.
The cable that came with the unit was not long enough to reach from the seat post to my stem mount phone pack so I used the one that came with my phone. Sliding the cable through the straps of my frame bag kept it out of the way and in place during my rides.
There is an LED light on the power button with three colors that indicate the Power Pack's battery level. Red is Low, yellow is Medium (around 50%) and green is close to Full (above 70%). The indicator light is lit while charging the unit or press the button to check the power level anytime.
The BikeCHARGE Power Pack doesn't have the high capacity battery power of the Anker Astro Slim2 but has enough to double your smartphone's use time. I like the fact that it can be mounted on the bike out of the way, is weatherproof/dustproof and can withstand any conditions I may ride in. The one negative I came across when using it was I had to stop and press the power button for 2 seconds to put it in charge mode to charge up my phone. Otherwise it worked as claimed and powered up my phone's battery to 100%.
Like the Anker Astro Slim2, the BikeCHARGE Power Pack can also be used with 5V input USB-charged devices like bike lights, GPS unints and GoPro cameras.
The Tigra BikeCHARGE Power Pack is available from Bike2Power for $59.95.
Disclosure: Anker and Bike2Power provided the review samples for this article, but offered no other form of compensation for this review.