It's possible to suspend to RAM such that it doesn't use much power. You'll need the BSP uboot images (not the mainline ones), and either the BSP 4.4 kernel, or the latest 5.7 development kernel that's being worked on.
I've got mine to a point where it uses about 2% battery sitting asleep overnight, which I consider entirely sane, but it was far from a easy process to get there.
I'm working on a tutorial to do it with Ubuntu, but it's definitely not a "just works out of the box" thing for all the distros.
https://forum.pine64.org/showthread.php?tid=10228 has some discussion on it - that's where I've been doing some of my work.
I've got mine to a point where it uses about 2% battery sitting asleep overnight, which I consider entirely sane, but it was far from a easy process to get there.
I'm working on a tutorial to do it with Ubuntu, but it's definitely not a "just works out of the box" thing for all the distros.
https://forum.pine64.org/showthread.php?tid=10228 has some discussion on it - that's where I've been doing some of my work.