In my last post, outlining the release of Catalina, I covered the process to check for 32-bit apps on your system prior to upgrading.
Here’s the info as a separate post, just so it might be easier to find.
To list all of your 32-bit software, go into the Apple menu > About this Mac > System Report… you’ll be taken into the System Information app (or just launch it from Applications > Utilities instead)
In the System Information App, down the left-hand side, find the Softwareheading. Underneath Software, click on Applications. Expand the width of the window so you can see the column heading for 64-bit (Intel) and click on it to sort by 32 or 64-bit.
Check for apps that say No and this is the software that will not run on Catalina.
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In my case, there were two apps from Apple that I’m confident will be updated when I update the Operating System. There are also a whole lot of apps from Adobe as part of Creative Cloud 2018. I haven’t upgraded to CC 2019 however Adobe have published a list of which apps are and aren’t compatible with Catalina. From browsing their list, all of the major apps in the Creative Cloud suite are 64-bit compatible.