iOS project, importing images takes all my life

Hello there. I have a project with around 300 pictures in jpg and png format. Some pictures have small size (107x107 and little more), other pics have full hd size.
I have to create unitybundle, and after that, Unity has switched to Web platform, and when I try to switch it back to iOS, Unity is “processing” all images, and this processing takes 2 hour (!) for less then 50% of all pictures! And while it processing, my CPU (i5 650) is loading too strong (about 100%).
Why it so? Is it normal behaviour for Unity?
p.s. sorry for my bad English

It’s normal for Unity to take a while to process assets when switching platforms. I agree that it’s quite annoying, though I never had to wait 2 hours…

There are a few solutions, but I never tried them. There’s an asset called Fast Platform Switch, which might be useful. There’s also the Cache Server.

I don’t know any free assets that can accomplish the same thing. One idea I had, was to duplicate the project and specify the platform in each one. this isn’t an elegant solution, but it might work to your advantage.