Apple has also introduced the range of new straps which will work for the series 3 and older models except ceramic grey option for the apple watch series 3, which won't be available for older models. both of these models are water resistant with 50m, which is great for those who don't want to take off their apple watch during the shower or for those who are swimmers.
Specifications (apple Smartwatch series 3 vs series 2)
apple watch series 3 improves further over apple watch series 2 S2 dual-core wearable chipset, which was a huge upgrade in terms of performance and battery efficiency in last year over apple watch series 1.
with smartwatch series 3, apple has introduced a new s3 processor that promises the 70% further improvement in performance over the s2 processor in apple watch series 2. the new w2 chipset is developed considering better wireless connectivity, which improves the power efficiency by 50% over the series 2 and 85% performance improvements for wi-fi connectivity.