A fully charged 10,000mAh power bank should charge an iPhone 2 – 3 times from zero to full charge, before needing to be recharged itself. It should charge most modern Android phones 1.5 – 2 times from zero to full charge. This 20W power bank can charge your phone faster than a standard 10W power bank. 
The rugged design makes it a good option for outdoor as well as everyday use. Recharging the power bank via the Type C cable provided will give it a nice, fast charge, while the solar charging is quite slow, and simply functions as a back-up option when you don’t have power available to charge the power bank, or if you’d like to leave it charging with exposure to sunlight for a period of time.