Apple has released the second beta of iOS 11.3 to registered developers (a public beta is likely to follow soon), incorporating the promised Battery Health feature that should provide users with more insight into performance throttling that occurs on older batteries. As one might expect, the new feature can be accessed from the Battery section of the iOS Settings app, and provides a percentage indicator showing the battery’s relative health compared to when it was new, along with a section on “Peak Performance Capability.” A note at the top points out that batteries come less effective as they age, and provides a link to an Apple support article on iPhone Battery and Performance.
There have been few other changes in the second beta of iOS 11.3, which otherwise just continues to refine the features previewed by Apple and included in the first beta, although iOS 11.3 beta 2 appears to be unavailable for the sixth-generation iPod touch and notes that iPhone X users will need to use iTunes 12.7.3 or later to perform tethered updates or restores and that using older versions of iTunes may affect the functionality of features such as Face ID.