If you have a Mac, you can use Quartz Debug to enable HiDPI mode on a non-retina screen. I wouldn't attempt that if you have anything but an iMac or large exter

If you have a Mac, you can use Quartz Debug to enable HiDPI mode on a non-retina screen. I wouldn't attempt that if you have anything but an iMac or large external monitor though. Alternately, get an iPhone 4 or one of the older retina iPod touch models. I picked one up for $80 to do some testing on.