All power banks are portable charging devices that offer a convenient solution to the problem of short mobile phone battery life. They allow you to charge your mobile phone and other devices via USB, so you can have power whenever and wherever you need it. Power banks have a limited number of charging cycles before they need to be recharged, which depends on the number of devices being charged at the same time. The capacity of a power bank, measured in milliampere-hours (mAh), determines how many charging cycles it can provide before needing to be replaced. Some power banks even come with multiple ports, allowing you to charge multiple devices simultaneously. With a power bank, you can have peace of mind knowing that you'll never run out of power for your mobile phone or other devices.