I never carry a charger for my phone or laptop unless I plan to spend more than a day out (I had to with my old laptop, though). I actually feel a little frustrated when my phone's battery lasts less than 48 hours, because it means I'm using my smartphone much more than necessary. I don't try to limit my phone use, but I do take some measures that probably help to save battery: screen rotation and bluetooth are always off and I use an app that automatically adjusts screen brightness much more efficiently than the stock android setting does.