Apple Watch Series 3 shows little change from Series 2 Watch, some redesign to accomodate LTE, and 1.07 watt-hour battery, up from 1.03 in Series 2 Watch
Tools Featured in this Teardown — Introduction — The Apple Watch is one step closer to a super spy accessory with its Series 3 capable of making phone calls.
Context & Ripple Effects
Apple shipped the Series 3 just days after its September debut at $399 with the same casing as Series 2 and a new W2 networking chip, and early reviews were already flagging the cost of that packaging: The Verge found battery drain with LTE and no Apple Music streaming yet, while the Wall Street Journal hit connectivity problems on at least two carriers in two states.
iFixit's teardown supplies the physical explanation for those complaints. Compared with the original 2015 teardown that revealed a 205mAh battery and Apple S1 CPU, the Series 3 keeps the Series 2 footprint almost intact — the battery grows only from 1.03 to 1.07 watt-hours, with the internal reshuffling spent making room for the LTE radio rather than runtime. Later generations would keep nudging capacity upward, as the Series 6 teardown showed with modest per-size gains.
First-order effects
- Buyers paying the $399+ LTE premium get confirmation that the untethered-call capability was squeezed into an essentially unchanged enclosure, which is exactly where the reviewers' short battery life came from.
- Repairability watchers gain a parts map for a watch whose battery remains user-replaceable through Apple — relevant given the roughly three-year lifecycle Apple cited back in 2015.
Second-order effects
- Because the WSJ's connectivity failures were carrier-specific, Apple's untethered pitch now depends on carrier network quality as much as its own hardware, putting carrier performance into the product review loop.
- The near-flat battery budget forces the next generations to buy runtime through incremental capacity gains — the pattern the Series 6 teardown later confirmed — rather than through bigger cases.
Third-order effects
- If the pattern holds, teardown-measured battery increments become the gating constraint on how much radio and sensing each smartwatch generation can absorb without sacrificing the all-day claim, keeping industrial design conservative even as features compound.
The trend: Cellular smartwatches are trading battery headroom for radios inside fixed casings, with each generation's feature load paced by small, teardown-visible capacity gains.