Adding the battery saver toggle to the Quick Menu on your iPhone can help you access this feature easily and quickly. To add it, follow the steps below:
1. Open the Settings app on your iPhone.
2. Scroll down and tap Control Center.
3. Tap Customize Controls.
4. Locate Battery Saver under More Controls and tap the green plus icon next to it.
5. Once added, you'll see the Battery Saver toggle icon in your Quick Menu, which you can access by swiping down from the top right corner of your screen.
At this point, you'll be able to turn the battery saver on or off with just one tap, helping to extend the battery life of your iPhone when you need it most.