You don't expect a brand new iPhone to share many similarities with older devices, but a teardown of the new iPhone SE by repair specialists iFixit shows that the new iPhone SE shares a lot of parts with earlier iPhones.
And there are a lot of components that are interchangeable with the iPhone 5S. The speaker, vibrator, SIM tray, and the entire display assembly, including the LCD, digitizer, front camera, earpiece speaker, and proximity sensor are all identical. Apple no doubt reused these parts to reduce R&D costs, which in turn keeps the cost of the device down.
This means that there are, in fact, few new parts. The logic board, rear-facing camera, Lightning connector assembly, and battery are all new parts.
The battery is particularly interesting. The iPhone SE comes with a 3.82 V and 6.21 Whr battery, which offers slightly more juice than the 5.92 Whr pack found in the iPhone 5S, despite the two batteries being identical in physical size.
Chip-wise the iPhone SE has some new components and a lot of components that have been found in earlier iPhones:
As far as repairability goes, there's good news in that the display and battery are easily accessible and removed, but bad news in that the Touch ID ribbon cable is easily ripped, and Apple still uses Pentalobe screws to hold the device together.
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