I may watch a video from time to time, but most of my interaction is surfing web pages where your constantly touching and swiping which includes the digitizer being used with the display, which translates to more battery drain. That and I don't have the greatest of signal in my home (use a network extender but I wonder if it being a 3G signal rather than LTE is causing higher battery drain as well).
Yep.. exactly. The more you interact with the phone, the more power it uses. Now, short of resource intensive games, if you are constantly navigating, that uses a fair amount of power... it's called "TouchBoost".
Not to go on a tangent here, but I hope it'll help some understand a little bit more of what goes on. Your phone has software (the kernel) that controls your hardware and uses dynamic frequency scaling - a fancy way of saying that it speeds up and slows down the processor speed - based on the resource needs. If the phone's just sitting there, it'll try to drop all the CPU cores down to their idle speed.... and if you load up Asphalt 8, it'll open it up. But it's all that in-between stuff that people notice most. You know how a phone sometimes coughs and hiccups a bit when you first touch it, then smooths out? Some will call that 'lag', but most often the case, that jank is coming from the phone ramping up the processor's speed.
So to avoid having the phone cough and spit while you are scrolling through G+, there's a mode in the kernel that Qualcomm calls "Touch Boost". What that does is scale the CPU speed up to a fairly high level as soon as it detects that you touched the screen, then holds it there for a few seconds to make sure it's ready for the next time you touch it.... So its a double edged sword... Touchboost makes the phone feel nice and smooth, but it is also indiscriminate and doesn't really care if you actually NEED that much processing power or not.... so you might be using more power than you would otherwise need. Here's two shots... the first is my phone at 'idle'. The second is just me touching the screen. (the top "LITTLE" cluster is the smaller, more power efficient cores and the bottom "big" are the more powerful A57 cores)
Now, just the act of touching the screen pushed the LITTLE cluster to 1344MHz, which isn't that far off from the 1555MHz full speed for the LITTLE cluster. Even the big cluster got bumped up a couple of steps. Does the phone NEED that much power for me to scroll through a very light kernel management app? Nope.
Now, on custom kernels, you can fuss with these settings, turning off Touchboost and instead using the governor to set the CPU speed based on demand.
Ok.. sorry for the thread jack.... but I hope this helps you understand why just scrolling around in an app that shouldn't consume a lot of power consumes a lot of power.
