Mac developers have a lot to think about as we close in on 2025, theeighth Mac developer survey from Setapp suggests. Should they sell software outside of the App Store? Is it time to diversify to other platforms? When will it be time to build software for visionOS? And what about artificial intelligence (AI)?Should they sell software outside of the App Store?Apple is being forced to open up to competition to the App Store, includingsupport for third-party app portals. As these stores appear, it seems inevitable that some developers might consider selling software at those new outlets, including Setapps own mobile app store. The data suggests that as many as a third of developers are ready to use third-party stores for iOS apps.Its a little different for Mac applications just 20% of those are sold exclusively via the Mac App Store, with 37% sold outside of that structure and 44% sold through both outlets. The implication here is that iOS app sales might end up in a similar stance, with the vast majority of apps made available via the App Store, rather than outside of it.The most popular channel for Mac app sales outside of Apples store is, of course, via the developers own website though when it comes to making those sales, the challenges remain much the same as before: app discovery, marking, and user acquisition. Ill be interested to see how third-party app stores rise to the challenge of helping developers with those challenges in future.Theres an interesting side insight here.Despite years of complaining about Apples 30% fee on apps sold through its own store (really, it is around 15% for the vast majority), it strongly appears developers believe it is worth sharing revenue with app retail services. That, once again, means the only real question behind of the App Store liberation remains the same:How much is fair to charge?That amount differs, but people seem pretty certain that revenue sharing is good for business, and a good chunk of them plan to stick with the App Store.Is it time to diversify to other platforms?If Mac developers are a barometer, then it looks as if the majority of Apples developers are willing to build cross-platform solutions to bring in new business, though most prefer to remain in Apples ecosystem. Three-quarters (75%) of developers build for other operating systems, mainly for iOS (59%), iPad OS (37%), and Windows (23%). Just 11% build for Android slightly lower than those building apps for Apple Watch.The trend is that diversification is taking place mostly within Apples own ecosystem, withsome Windows development. What isnt happening fast so far is visionOS, which hasnt yet become a large enough platform for mass market app developers. Its aprofessional tool.When will it be time to build software for visionOS?Twenty percent of Mac developers plan to develop for visionOS in 2024 or are already in the process. Low market share and high device price remains a concern and is possibly why almost half (45%) of developers havent decided whether to build for the platform yet. Thirty-five percent of developers say they will not build for the platform this year, though 8% are building visionOS apps already.Whats interesting is that while it confirms relatively low interest in developing apps for Apples newest hardware at this time, it shows interest sufficiently high that almost one in 10 Mac developers are already building for the platform.This bodes very well as Apple improves the hardware and reduces cost, as it means there will already be a decent number of apps available by the time it inches toward being more mass market. While there are many developers who wont use their resources to build right now, things can and will change as the situation evolves.What about AI?Apples spatial reality party was to some extent dented by the near-simultaneous revolution of generative AI. If Apple had expected visionOS to grab the oxygen from the room, it only had limited success. Sure, the rest of the industry went into stasis as it awaited news of VisionPro, but AI grabbed headlines everywhere and developers are far from blind to that. Nor, asApple Intelligence proves, was Apple.This is probably why more than 41% of Mac app developers are about to begin using AI models in their apps, with another 19% thinking about it. What they are using AI for is interesting. As youd expect, personalization and automation are big trends, but real-time translation, automated IoT deployments, and productivity tools in various stripes seem to be shades of whats coming as apps get updated in the coming months. AI/ML development is by far the trend developers think will have the biggest impact on their apps in the year to come, with personalization and privacy rules also in the picture.Theres a lot more that should be of interest in theSetapp survey this year. But what seems to be crystal clear is that the intelligence in devices will be harnessed in rapidly more sophisticated ways in the months and years ahead at what point will AI predict your needs to the extent that App Stores will be redundant? And as apps continue to evolve into becoming cloud-based services, will operating systems mean as much anymore?You can follow me on social media! Join me onBlueSky, LinkedIn,Mastodon, andMeWe.