Imo that's pretty unethical. If you don't want ads, use an app where the maintainer has decided not to include ads or not to charge.
But don't take something from a sole-developer (meaning in this case labor is actually getting all the fruits of their labor instead of a CEO), use one of the other options instead where the developers aren't using it as their main source of income.
True, but I found Jerboa to be very unpolished and barely worked so I crawled back to Reddit. Now that Sync for lemmy is released I feel right at home.
Was that during the period of time they couldn't upgrade lemmy.world? Been stabe ever since the upgrade was done and the servers tuned. For me it is the most RiF like of all the apps, so I prefer using it.
Personally, I love the UI/UX of it and how customizable it is. For me, it's unparalleled, and I'm happy to pay for it to support the independent developer behind it. But I get that not everyone cares about it and would rather use a different option, and it's cool that there are so many different options to interact with the fediverse.