Nokia relicensed it to LGPL 3. Bindings for other languages can have another license though, obviously. For example, the Python PyQt bindings are licensed under GPL or a commercial license.

Yeah, either you make your whole project GPL, or you buy a license so you can make your code proprietary/non-GPL.

I thought LGPL meant if you link to (Qt) shared libraries, your project does not have to be LGPL ?

You're right, Qt is available under LGPL 3.0 now.

https://www.qt.io/licensing-comparison/

Not all platforms allow for dynamic linking.

Out of interest, which platforms that Qt targets, cannot have dynamic linking?

Embedded devices, car infotainment systems, iOS (only dynamic frameworks from Apple are allowed).

If you are targeting ios you are already paying Apple for a developer account, so paying Qt basically just doubles the license cost. Everything else is fairly exclusively corporate, where Qt licenses are a non-issue.

I don't see an issue paying for Qt, other professions pay for their tools.

I was just giving an exemple where LGPL isn't possible.

iOS allows dynamic libraries these days. Granted, it didn’t allow for them for a long time, but since iOS 8 you can use dynamic libraries just fine.