Other posts are talking about iPhone6 and 6 Plus screenshot size for iTunes Connect
iPhone 6:
- 750 x 1334 pixels for hi-res portrait
- 1334 x 750 pixels for hi-res landscape
iPhone 6 Plus:
- 1242 x 2208 pixels for hi-res portrait
- 2208 x 1242 pixels for hi-res landscape.
However they have to be uploaded without the status bar, so these dimensions do not look correct.
iTunes Connect Developer Guide gives different suggestions for 4S, 5 in case of including or not including the status bar, but not for the iPhone 6 and 6Plus, for which only the full size are provided.