iOS Deployment

A new problem arose for me today, meaning things worked ok when I did the same thing two weeks ago. I wanted to deploy a newly built app to my iPad (version 3) running iOS 9.3.2. I opened Xcode and attached my iPad to my iMac (2008 or so) running OS X Yosemite 10.10.5.
When selecting my iPad within Xcode 7.2.1, it said “Could not find Developer Disk Image”. I skimmed through Paul’s iOS deployment video and checked out several web comments, but didn’t see a fix that seemed doable. One suggestion was that iOS 9.3 requires Xcode 7.3. But Xcode 7.3 is not an available upgrade for Yosemite. Also, it appears that my computer can’t go beyond Yosemite, although I am not sure of that. Am I missing something obvious? Is there a way to get this to work with my configuration? Like I said, I was able to deploy an earlier version of my app just two weeks or so ago.

ElCap will run on a 2007 or newer iMac… so it might be time to think about upgrading

It does not cost much to got to the App Store and try to get El Capitan.

There are lots of macs that will run el cap that wont run sierra
iMacs have to be late 2009 or so at least

I have iOS 9.3.2 on my iPhone and get the “Could not find Developer Disk Image” message when connecting to an older version of Xcode. Xcode still allows me to install my apps.