Is there a point in supporting projects?

I would agree I’m doing good by FOSS projects (that Google themselves need or build) by paying Google, if I’m a Google loyalist.

My point is about the developer aspect.

Like mentioned above, some FOSS projects are “gifts”. These developers don’t expect any substantial gain nor do they expect to commit to maintain it. A very different thing to FOSS projects for which developers work on their free time (or even full time), where donations / sponsorships done directly does matter.

My point is about the developer aspect

Right, that makes sense — I hope you find joy in what you do, whether it’s because of the community or the technology. The least I can say is: I tried the app and found it well designed.