After updating to Mojave, many Mac users see a message saying that an app they are trying to use needs to be updated and won't work with future versions of macOS. By future versions, that means the next major update of macOS, probably coming in late 2019, not minor updates. Before then, you can update to a newer version of that app, or find an alternative app to use in its place.
The first misconception people have is when they see this is now my app is no longer compatible with my Mac. That's not true! This is a warning. This says this app will run and you can still use it. But in the future you won't be able to. By the future it means the next version of Mac OS. The next full version. So probably what comes out later this year probably in the Fall. Not the next small release or update or something like that. So, as long as you continue using Mojave you will be able to use this app. It's just warning you that the next thing to come after Mojave won't.
So why is this happening? Well, if an app gets very old without being updated it's still in 32 bit mode. Now, Macs have been 64 bit for a long time. As a matter of fact in 2010 when Mac OS Lion came out that operating system was 64 bit. So you needed a 64 bit Mac to be able to run Lion. So any Mac you bought from 2010 on, as a matter of fact even a little bit earlier than that, could run 64 bit apps. But for a long time, and up till now, Macs can run both. 32 bit and 64 bit apps. The operating system supports that. So if a developer failed to update their app over all those years and kept it as a 32 bit app, then you could still run it.
But at this point the only apps that are still 32 bit only and not compatible with 64 bit are apps that have been abandoned. The developer is no longer updating the app. They haven't created a new version for awhile. Maybe the company doesn't even exist anymore. Or perhaps they have updated their app but you failed to follow those updates. So you're using an earlier version even though newer versions have come out. That's the most common thing that people have now. They're trying to use an old version say of Microsoft Word or something and they don't want to update to the newer version. They don't want to spend the money on it and now they find out that this old version gives them this message sometimes. They could still use it but at some point they should update.
So there are a lot of reasons why you should keep your software updated. You get not only the latest features but also security update and stability things. If you've got an app that old that it's not 64 bit at this point then it's probably not working the best. Maybe features that aren't working. Maybe times when it crashes. Things like that. Who knows what kind of security vulnerabilities could be there as well. So it's important to keep your software updated.
An option to updating is to find a different app. So if you were using an expensive app and, you know something like say PhotoShop or Microsoft Office, and you want a cheaper version that does the same thing, maybe take a look at using alternatives. For instance if you're using Word but you really don't need to be in the Microsoft ecosystem use Pages. You already have that. If you're using PhotoShop but you don't want to go and buy a new version of it or subscribe to an Adobe service, then maybe look at using one of the many apps in the App Store like Pixelmator, Acorn, Affinity, one of those for editing images. Or maybe just use the stuff in Preview or in the Photos app to edit your images and not have to pay anything.
So Apple actually has a page where they go into more technical details about this alert. It actually goes back to High Sierra. High Sierra gave a warning and Mojave now actually gives a more stern warning saying it's not going to work in the next version. So you get some details if you want to go to this page.
Now if you want to check to see if you have any apps that fit into this one way to do it is to go to About This Mac and then go to System Report. Under System Report, I already have it selected here, there is Applications and you get a list of Applications. Expand this window to full size and you can see here there's a column for 64 bit. So you can Sort by that. So if you sort by it you can see all the No's. They're the ones that are going to give you this message.
Now I have a lot of stuff there. Why? Because I'm a developer. So I'm constantly creating things that are identified as apps. So I have, in my Archives, all sorts of projects from the past that you won't have that are saying no, no, no because, you know, I've got an archive version of an app I created in 2007. That kind of thing. That's going to show up here.
Chances are you might see just a few apps. Look for a version number. If it has a version number and it's no then it's probably an app that you have that you could in launchpad and things like that. Now you can go through this and kind of get an idea. Maybe it's time to uninstall apps if you're no longer using them at all. Maybe time to look for newer versions or update or find an alternative to those apps. In some cases it's just a matter of the developer hasn't gotten around to updating them yet. Even bit developers like Adobe still have a few little pieces that they're going to need to update at some point this year. If you're using the current version of Creative Cloud I'm sure that it will all be taken care of by then.
But it is a good idea for you to go through it. For instance for me Adobe Fireworks is an app I loved. But it's 32 bit. They've abandoned it. It's not going to work in the next version of Mac OS so I have found a great alternative that I'm using instead and I'm ready to move on from Adobe Fireworks. So go through those. Don't fear that message. There's nothing you need to do right now. You still have probably eight, nine, ten months before there's another version of Mac OS that will actually make these apps so they don't work. So you're fine for now. If you have an older Mac it may be that Mac OS Mojave is the last version you're going to update to anyway.
Now one thing to pay attention to is the fact that if you say I'm going to stick with Mojave just so I can run these old apps. That may be fine but your next Mac isn't going to be able to run Mojave. Right. If whatever is after Mojave is the current operating system new Macs only run on the operating system that exists there when they came out and forward. They don't go back. So eventually you're going to have to find a solution. If an app has been abandoned by the developer or you're unwilling to pay for an update it's time to find a solution now while you can make an easy transition rather than being forced into it when you suddenly have to get a new Mac one day or decide it's time to update for other reasons.
Apple Link: 32-bit app compatibility with macOS High Sierra 10.13.4 and later.