There have been many, many threads on ways of obtaining the best battery life from the S4 and indeed other phones. The answers all come from users with their own personal views as to how to achieve this.
Have any of the manufactures of those batteries offered their expert advice (as opposed to opinions of end users) as surely they are the ones to provide an accurate reply?
Have any of the manufactures of those batteries offered their expert advice (as opposed to opinions of end users) as surely they are the ones to provide an accurate reply?