Macworld When you’re out and about, it’s always a fantastic idea to have a portable power bank on you because you never know just how fast your phone will drain. The Anker Nano portable charger is a fantastic choice since it’s only $18 at Amazon, down from $26, and it’s the best price yet. This is a super compact portable power bank that will even fit into women’s pockets. I just recently got one of these, and it performed super well, keeping my phone alive during a Coldplay concert. The Anker Nano has a 5,000mAh capacity, which should provide you with a full charge for your device – or pretty…