问题
Wondering if both a high res and low res image are required for iPhone Apps. Having a duplicate copy increases file size which is something I need to cut down.
I've built apps in the past and only used high res, without @2x appended to the file name. The apps look great on Low res and High res devices. so...
Let me know
回答1:
It is not required to have both image types. However, since the resolution is different for the Retina display you might build a Default image that looks nice on the iPhone 4 showing lot of details, but will look different on the other iPhones due to lack of correct resolution. Furthermore the image will be downsampled and if your UI fetish is big enough you rather provide two images than only one very good and take an accaptable sampled image.
I'm not sure if it is the best approach to skip one image just to reduce file size because most of the time the Default images are not the most relevant media part, since icons, sound files etc tend to use more space.
To conclude: I would suggest using both images and try to reduce the App size somewhere else.
来源：https://stackoverflow.com/questions/6229795/is-a-copy-of-a-high-res-and-standard-res-required-for-iphone