Though you may still use iPhoto to manage photos on your Mac, this true that iOS no longer supports iPhoto for syncing photos. You will have to get the new Mac app known simply as "Photos". There is an Apple support article that specifically addresses how to update iPhoto to Photos, and how to manually migrate your photo library to the new Photos application. Here is a link to the article in question.
Updating from iPhoto to Photos for OS X - Apple Support
As for iPhoto, there are no more updates for that application here in the U.S., because the app has been fully replaced by Photos. The good news is that the app should recognize your existing photo library. Keep me posted about your issue and I will see what other options we can explore to hopefully get a solution.