Marco.org

Grant “chpwn” Paul, possibly the most qualified person in the world to talk about things like SHSH blobs, on the difficulties I discussed in this week’s podcast of getting and maintaining devices with old iOS versions:

Since I spend my time with those (admittedly hacky and confusing) tools and have an understanding of how the restrictions here work, I thought I’d write an explanation and a guide on how to successfully test for older iOS releases.

The inability for developers to install old OS versions on test devices makes supporting anything but the current version very difficult. As much as Apple would seemingly like to believe that it’s unnecessary to support anything but the latest OS, most developers continue to support versions at least 12–18 months back.

That said, last week’s release of Instapaper required the 6-month-old iOS 5 for the first time, the most aggressive minimum iOS age I’ve ever required, and it has received surprisingly little negative feedback. Requiring the over-a-year-old iOS 4 last fall was met with much more customer hostility.

Maybe Apple doesn’t care about letting us test on old versions because we’ve already worked around the problem sufficiently: small developers don’t usually need to support old versions for long, and large developers can keep boxes of old iPhones and iPads around for testing, having paid or hacked whatever was necessary to acquire them with (or revert them to) old iOS versions.