Do I need to design on Sketch for all iPhones & iPads?

Hello,

I'm new to Sketch and I'm going to design an app for iPhones and iPads. But, I'm wondering how one design (iPhone 8 for example) would work on iPhone 7, 6 and iPhone X and the newer generation. Please advise :)

Thank you
Sketch is an independent app, not a developer tool for this forum.
You should ask them directly.

In addition, I do not understand your point. Why would ever sketch be needed to design an app ?

I've developed a lot of apps, that work from iPhone SE to iPad 12.9, without even thinking of using Sketch.

To design for multiple iOS devices formats, just use the layout tools of Interface Builder appropriately.
Do I need to design on Sketch for all iPhones & iPads?
 
 
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