The newly designed battery pack for the iPhone Air has a slimmer profile compared to its predecessor, making it thinner and longer. This design allows the battery pack to fit closely along the back of the phone without interfering with the camera bar. Despite a reduction in potential battery size due to its slimness, the new pack is reported to feel more balanced in hand, as opposed to the bulkier older version.
However, the introduction of this battery pack does come with certain limitations. When attached to the iPhone Air, it increases the phone’s overall thickness, resembling more traditional iPhone models. The battery pack is slightly thicker than the iPhone Air itself, which may mitigate some of the sleekness associated with the new phone design, although it isn’t overly cumbersome in initial handling.
Furthermore, this battery pack is designed exclusively for the iPhone Air. While it can technically connect magnetically to other models, its size is tailored specifically for the iPhone Air, limiting its compatibility. For instance, it may fit the iPhone Pro Max but is unlikely to work with the smaller models, as they feature different dimensions.
In terms of aesthetic and functionality, the new battery pack retains a similar style to the original, featuring a lightweight design and a soft matte finish. A small light indicator near the bottom provides feedback on the charging status when attached. There appears to be interest among consumers for Apple to extend this design to other iPhone models or for some to choose the iPhone Air specifically for this battery pack option, despite potential limitations in overall battery performance.
Source: https://www.theverge.com/apple-event/775048/iphone-air-magsafe-battery-pack-hands-on-photos