Yep. If it uses a cloud service, they're probably going to squeeze you, pull a bait-and-switch, or go out of business. The only exceptions that spring to mind are services with significant monetization in the corporate space, like Dropbox. And I'm not really confident that Dropbox's free tier will remain viable for long, either.

Even non-cloud-based apps are risky nowadays because apps don't remain compatible with mobile OSes for very long. They require more frequent updates than freeware/shareware generally did back in the 90s. I remember some freeware apps that I used for 10 years straight, across several major OS versions, starting in the 90s. That just doesn't happen anymore. I've been using Android for over 10 years and I don't think there's a single app I used back then that would still work.

Single-purchase apps are basically dead, at least on mobile platforms. Closed-source freeware is dead, too. If it's open-source, if push comes to shove someone can always pick up the torch and update it. It's very rare for an open-source project to be completely abandoned without there at least being a viable open-source alternative available.

At this point, I don't even look at Google Play. It's F-Droid or bust.