ISO APP what should the DPI Be

Yes i'm trying to get to my developer my Icon and Splash Screen for our APP. (I provided them some older ones and they look baddly pixulated on my iphone4


1. How do I set up my file in Photoshop do I do this

example 180x180 DPI ???????


2. I have read Apple Docs Table 45-1 on Also do I need to make an Icon for all of these sizes?
iPhone 6s Plus and iPhone 6 Plus (@3x)
180 x 180


iPhone 6s, iPhone 6, and iPhone 5 (@2x)
120 x 120
iPhone 4s (@2x)
120 x 120


iPad and iPad mini (@2x)
152 x 152


iPad 2 and iPad mini (@1x)
76 x 76


iPad Pro (@2x)
167 x 167


I Also see I need a Launch File again i see all the sizes I need to provide my deveopler. but what DPI again.. is it the standard 72 dpi..


3. What is the @ 3 @2 or @1 mean cant' figure that out


Thanks

Photoshop doesn't know that much about iOS images - best to incorporate the devrocket plugin in that case.


@2x, as an example, is used by retina devices.


As well, see:

https://developer.apple.com/library/ios/documentation/UserExperience/Conceptual/MobileHIG/IconMatrix.html#//apple_ref/doc/uid/TP40006556-CH27-SW1

ISO APP what should the DPI Be
 
 
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