New iPad’s Retina display: how to reduce image file size?

Even till the day of the Keynote about the new iPad, I couldn’t believe the rumours telling the new iPad will have a Retina Display. I thought it was a too big challenge for the Apple engineers to make a resolution of 1536 x 2048 pixels was workable for a mobile device. I was waiting for Apple coming with some smart solution to up the screens resolution, without doubling the size in both directions. Apple actually surprised me by releasing the new iPad with this ridiculous big screen. As a user, this was off course fantastic news! As a developer, just doubling the size of my artwork wasn’t enough.

When I started working on my first app update to support the Retina display, I found out the hard way that just doubling the size of my images and including them as ‘@2x’ images blew the size of my app completely out of proportion. Mosaic Wallpaper Designer currently takes 5.5MB of your space to download it from the App Store. After I have included my reworked images, it grew to around 45MB! Even though this is an universal app and most of the UI is already in Retina resolution to support the iPhone 4 and 4S.

As a coder, I had to search for some tricks to reduce file size of my graphics to make the the file size workable again. Because I don’t think I’m the only one facing this kind of problems, I would like to share some of my experiences with you. For people with a graphical background, this may be pretty obvious, but this article is more targeted at Independent Developers without much of a graphical knowledge. If you have any additions to this article, add a comment below or contact me!
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