Battery Saving App
I am planning on buying a new Android phone in place of my old ageing Samsung Galaxy S3 LTE. I'm choosing between the Nexus 5, HTC One (M7) and the Galaxy S4. One thing that is common to these phones are they both have Snapdragon processors.
My question is:
1. Is it wise or even practical to even install a battery-saving app for these phones? (as I heard such apps does help but also is a drain to the batteries themselves and resources/RAM)
2. What battery-saving app would you guys recommend? (I know I can easily search in Google or the Play store but there are just hundreds of them. I want to trickle it down to the "best of the best" or the "top one" out there currently?