When I'm visiting my siblings and relatives who live 100 miles away, I'm often gone for an entire weekend. Instead of carrying individual power adapters for my iPhone and iPad Air 2, I simply pack a $69.99 RazorMax.
It allows me to keep multiple devices powered with one small accessory. The minimalist RazorMax can charge smartphones and tablets at the same time. However, since it's only four inches by 2.5 inches in size with a sleek, anodized, 0.38-pound form factor, it doesn't take up much room in my suitcase or backpack.
The RazorMax takes about 120-150 minutes to charge fully with a standard smartphone wall charger. The outputs are both 5V, 2.4A maximum, rated at 1.0A per outlet. That’s works fine for an iPhone, but is a bit weak for a tablet. My iPhone 6 Plus charged in just over 60 minutes; my iPad Air 2 took about 20 minutes longer.
Still, the rechargeable 600 mAh battery packs enough juice to provide hours of extra battery life. For example, on my iPhone 6 Plus, it provided an extra 26 hours of talk time. Its pass-through charging will charge the power bank itself and connected devices simultaneously. However, there are no included cables, so you’ll have to bring your own.
The RazorMax has a four-light LED battery indicator that, interestingly, you shake to check the battery level (each dot represents 25% of the battery; one dot is 0-25%, two is 26-50%). The folks at myCharge, the company that makes the power bank, says it maintains battery power for up to a year. However, I've not had mine long enough to verify that.
That said, the RazorMax is a handy utility when I’m traveling.