Apple is starting a screen replacement program covering the aluminum versions of the Apple Watch Series 2 and Series 3. It addresses a crack that may develop along the rounded edge of the screen, starting from one corner and then potentially spreading along the entire perimeter, as shown in the example drawings. The affected models are both 38mm and 42mm sizes of the Series 2 and 3 with GPS-only and GPS+cellular versions of the latter. Nike+ versions of both generations are part of the program as well. It's unclear what causes the crack to form and just what the "very rare...