On Surface Duo, tap Settings, tap Battery, tap the 3 vertical dots (...) in the upper right corner, tap Battery Usage, tap the 3 vertical dots (...) in the upper right corner, and then tap Show full device usage,.
A list of system level components and the percent of battery used since the last full charge will be shown
If anything besides Wi-Fi, Screen, and Mobile network standby that has a high percentage of use then check the battery optimization for these apps.
Click any app and then tap Battery Optimization, this will open a screen that shows a list of apps that are not optimized for battery. If there are any apps that you use besides Phone, Messages, Google Play services that are used often please ensure to close the app after use and then see if the battery life improves.
This is an excellent recommendation for how to improve battery performance. Most of the time running apps use battery power at will, especially those that use push notifications which require constant communications between the device and the app's servers. Other are just plain power hogs. For example, the Twitter app uses an extraordinary amount of power when I use it. To alleviate this I always force close the app so that it does not run in the background, thus using power that it should not be using.
I am a heavy Edge (including video), YouTube, MSN News, Twitter, etc. and streaming services (like Netflix) user, and routinely have two applications active (one on each screen). I periodically close all open apps, especially when I am not actively using the Duo. I turn off notifications for apps that don't need to use notification except when you're using them. I don't have Bluetooth running unless I need it. I have battery saver on. Also, by limiting startup apps (those 3rd party apps loaded into memory at startup because they think they own the device) I was able to improve battery life significantly because those apps don't load until I launch them. (There's an app in Google Play that allows you so set these loading defaults. I use one called Task Manager
- Process & Startup Manager by Neon Team.) I also have an app that allows me to adjust the screen brightness using a widget on the home screen which allows me to set the screens' brightness to what is necessary and thus reduce battery usage.
If I start with a full charge when I get up in the morning, by early evening I usually still have around 60 percent battery life. Yes, this requires some thought and minor effort on my part but it provides the battery life that more than adequately takes care of my needs and allows me full functionality of this terrific device.