I’ve just got a new iPhone 7 and while I am loving the transfer from Android, the battery backup and charging time are irksome. I looked around some and realised that 12W chargers work much better than the 5W one supplied with the phone. So I was planning to get the Anker 12W charger - https://www.amazon.com/gp/product/B072K6BLJJ/ref=oh_aui_detailpage_o08_s01?ie=UTF8&psc=1 instead of the more expensive but not necessarily better quality iPad one. However, I wonder if there may not be a method in the madness in the decision to supply a 5W charger? Does this not ensure a much longer lifespan of the battery, especially since a lot of users keep their iPhones for more than 3 years. Or are there other reasons such as cost for this decision? So I am wondering if I may end up negatively effecting the lifespan of the phone’s battery by shifting to a 12W charger? Thanks!