We're in a similar position, except that we did recently drop the money for a new iPad. FWIW, it's actually a nice piece of kit, as long as you don't mind playing by Apple's rules of course.
However, the browser idiosyncracies drive me nuts, and we spent considerable time not just updating all our graphics but also redoing way too many different parts of our HTML, CSS and JavaScript in order to get the high-res images to display properly and to have the correct version of each image download efficiently on both Retina and lower resolution displays.
Not all of this is Apple's fault. Some of it comes from limitations in the current HTML and CSS specs, which would apply to high-res displays on Android devices as well. But some of it seems to be entirely due to choices in how iOS Safari does things, and the problems aren't limited to high-res images.
I'm still not entirely happy with many of the solutions we are using. I think we have a practical workaround for most of the issues, but often the results behind the scenes are just nasty and hacky. And as you say, it has been vastly more work than supporting IE9, which required approximately zero extra effort.
However, the browser idiosyncracies drive me nuts, and we spent considerable time not just updating all our graphics but also redoing way too many different parts of our HTML, CSS and JavaScript in order to get the high-res images to display properly and to have the correct version of each image download efficiently on both Retina and lower resolution displays.
Not all of this is Apple's fault. Some of it comes from limitations in the current HTML and CSS specs, which would apply to high-res displays on Android devices as well. But some of it seems to be entirely due to choices in how iOS Safari does things, and the problems aren't limited to high-res images.
I'm still not entirely happy with many of the solutions we are using. I think we have a practical workaround for most of the issues, but often the results behind the scenes are just nasty and hacky. And as you say, it has been vastly more work than supporting IE9, which required approximately zero extra effort.