While not as eye-catching as Face-ID and other features, low-power mode has become one of iOS's unsung heroes. If you are not on a charger, you can turn this feature on to set the power and network connection to extend the battery life by up to three hours. If your device has a jailbreak, you can even automate the low-power mode to make sure the battery does not go down to critical levels while driving.
When this option is enabled, the SmartLPM of smokin1337's automatically turns on the low power mode when the iPhone is turned on and not in use to reduce the workload To keep the battery consumption as low as possible. The tweak can be adjusted even further, so that the low power mode occurs exactly when you want it.
SmartLPM has many advantages for your jailbroken device, as the low power mode does not need to be manually activated at critical moments. Most importantly, automating the feature helps keep your iPhone's battery from getting low over time, as it does not need to be constantly charged due to excessive battery drain.
: Install the Packix Repo  SmartLPM is not included in Cydia, which means you must first install a separate repo in your Cydia app to get it. However, the process is very simple: first open Cydia and tap "Sources" at the bottom of the screen to go to the Repository page. From there tap on "Edit" in the upper right corner followed by "Add" in the upper left corner.
A URL prompt appears after you click Add, so you enter repo.packix. com in the empty box. Click "Add Source" when done, and give the repo a moment to install. Touch "Back to Cydia" when the process is complete.
Next, click the magnifying glass icon in the main menu of Cydia and look for "smartlpm" on the following page. Select the tweak as soon as it appears in the result box. If you are in the Details Page of 1945 [Details] tap "Modify" in the upper right corner to proceed with the installation.
Then tap "Install" at the command prompt and press "Confirm" at the top – right corner of the following page. SmartLPM is now downloaded to your device. Wait a few seconds for the process to complete. Then click on "Restart SpringBoard" to finish the installation and complete the installation.
Now you have to automate Low Power Mode, go to Settings and tap on "SmartLPM" to get the ball rolling. Then tap the "Enable Tweak" switch to activate the function. Then make sure that "Low Power While Locked" is at least enabled. We also recommend that you enable the Disable Sleep Mode switch because you can now automate the options for this notification.
You can also automatically enter sleep mode when the battery reaches a certain level. Activate "Auto Low Power Mode" and then set the slider to the desired percentage.
With SmartLPM you can even change the threshold at which the low power mode shuts off again. For example, if you enable "Low Power While Charging" together with "Disable LPM At Set% (Charging)" and set the latter to 85%, the low power mode will automatically be activated when you charge your iPhone and turn off the iPhone once reaches 85%.