I recently took this 5k power bank on an overseas trip, and it was perfect! I used my iphone constantly each day for messages, maps, videos and photos. I did not want to lug a large heavy battery, when I only needed to top-up my battery. The Cygnett 5k was perfect for this, small, light weight, fits snug to the back of my iphone using magsafe. The iphone with the battery attached then fits easily in my pockets. Being 5k, it wasn't an issue going through airport security. Airlines now require rechargeable batteries be placed in hand carryon luggage, so small and light weight means this is not an issue. The Cygnett 5k is easily recharged overnight and has charge through, so I can recharge my iphone at the same time.