Apple's latest operating system, iOS 7, is frustrating a lot of people who just want to set their lock screen to their favorite wallpaper. People are complaining, for instance, that their iPad wallpaper, which wasn't stretched before the iOS 7 update, is now pixelated. Or it's not the right aspect ratio. Or there are black borders on each side of what was once a great lock screen image.

These problems arise for two reasons: First, Apple's parallax feature, which is meant to simulate true depth, needs to resize wallpaper images to work its magic. Second, particularly on the iPad, iOS attempts to find the best wallpaper resolution for both landscape and portrait modes, and that's where the stretching happens. Even more frustrating, iOS 7 really seems to want to position your wallpaper in its preferred way, and it won't let you reposition it.

Here's what you need to do to get your wallpaper just so.

1. Turn off parallax. You'll find the switch under Settings > General > Accessibility, and it will be labeled "reduce motion." This button changes a lot of the flashy default animations – instead of apps flying at your face, they tastefully fade in and out – and is highly recommended, even if your phone doesn't make you seasick. However, what we're interested in is that it (mostly) turns off parallax.

2. Use the correct resolution. A lot of people end up using photos they've taken as wallpapers. It should be fine, as most smartphone shots have more than enough pixels. But because they're not the iPad's preferred resolution, your system will still be guessing about which way to position the image. Fire up an image editor and crop the photo down to exactly what your device wants. Here's a nice chart that lists the resolution for your iOS device.

3. For the iPad, go square. Since a lot of the stretching issue comes from the iPad using the same wallpaper for both portrait and landscape orientations, you can forgo the guessing game by using a square wallpaper. Try using an image with a resolution of 2048 x 2048.

4. Embrace iOS 7 and make your own parallax wallpaper. If you like Apple's iOS 7 effects, an alternate option is to make special wallpapers that include enough extra "fringe" to work with the parallax feature. Cult of Mac recommends an extra 200 pixels on each side of the picture. However, if you want an easier process, use an app. Wallax will get the job done and it costs $1 on the App Store. Fix My Wallpaper is less polished, but it's free.

5. Complain to Apple! If you want the ability to scale down your lock screen image – as you were able to do with previous versions of iOS – maybe sending a strongly worded message to Apple will get the point across.

[Apple Support Forums h/t iMore]