Your Android mobile phone includes a built-in app to help you visually monitor the battery usage pattern. Go to Settings > Battery (the app’s location may vary for your version of Android) and you’ll see a history graph detailing which apps have been consuming the most battery power and how long you can use the device before the battery is completely drained off.
If you observe the Android battery graph more closely, you’ll find some other interesting details as well. For instance, you’ll know the pattern of your mobile signal strength, how often apps running in the background ‘wake up’ your sleeping device and so on.
This is the main battery graph and is easy to interpret. If there are any breaks, it indicates that the device was powered off during that period. If there are any red or yellow lines over the graph, it indicates that the charge was critically low during that period. The gray area represents the approximate remaining charge.
Related Tip: Do not let your phone’s battery charge dip the below the 10% mark as that will affect your phone’s battery life in the long run.
If you tap the battery history graph, it will provide a more detailed breakdown of the battery usage and charge times as shown in the screenshot below.
The colored bars in the Mobile Network Signal indicate the strength of signal (or number of cellular bars). The dark green bars indicate strong signal (full bars), light green is a good signal, yellow means a weak connection (3 bars or less) while the red bars indicate ‘scanning’ mode meaning the device is searching for a network signal.
If your device is in airplane mode, or when you are out of coverage area, the network signal block will be blank (white or, for some models, black).
The Wi-Fi block indicates the time when the radio was turned on though the device may not be actually connected to a Wi-Fi network. The colored strips for charging indicate the time when your Android phone was connected to the charger. The ascending slopes in the battery graph is also an indicator of the charging time.
The colored blocks in the Awake bar represent background apps that may be running even while the screen is off. For instance, your mail app periodically checks for new email even while the phone is in ‘sleep’ mode. If you notice any extended ‘awake’ blocks, it means that some battery-draining apps are keeping your phone active and should be uninstalled.
The GPS line indicates the duration when the GPS receiver is powered on and some app or system service tried to use GPS to determine your exact location. Finally, the ‘Screen On’ bar indicates the actual usage time when the screen was turned on and not in standby mode.
Also see: How Websites Detect your Battery Level