Apple have finally decided not to upgrade Aperture. Over the last few year Apple have ploded along just alowing Aperture to work only just in their operating systems. Once a user installs the upgrade to Mojaveyour copy of  Aperturewill cease to work leaving the app unable to work on your new OS. It has been known for some years since June 2014 when Aperture developement ended that the day would come but there was never any press release to say when.

If you want to find out more from the Aperture Communities then follow this link

If you would like to read the article by Rod Lawton then this is the link

If you want to find out how to migrate your Aperture libraries follow this link to apple for guidance.