User Profile

i am developing an apple pass(boarding pass) but the issues comes with logo.i don't know what size and resoltuion should be used for the logo to not get blurred on devices specially on retina devices. i am using 480 by 150 in logo.png and 2(480 by 150) logo@2x.png and 3(480 by 150) in logo@3x.png.the logo is looking perfect on angroid devoices but getting pixelating on retina devices n also i have read someehre on internet that for retina devices logo@2x.png automatically gets used but in my case pass is just using logo.png file even for retina devices and results in pixelation of logo.that all i could explain kindly help me out reolving this issuethank u!