The small business license is $499 and you only have to pay that if you want to statically link against QT without dealing with the LGPL. Dynamic linking Qt is the default, costs $0 and doesn't incur the wrath of the LGPL.

Static linking also costs $0 if you comply with the terms of the LGPL:

https://www.gnu.org/licenses/gpl-faq.en.html#LGPLStaticVsDyn...

Note that does not necessarily require “your code” to be/come open source.

Is that $499 per platform? I'm using Lazarus right now (after QT sticker shock). It's pretty good and free. I rather like object pascal. TMS has a webcore product that runs out of Visual studio (non free) which is also object pascal and generates an html/js SPA. i'm not affiliated with them at all. Just a fan.

Per developer and I think that covers all mobile and desktop platforms.

Thanks, I didn't know that. I looked at QT 4 or 5 years ago and dismissed too quickly apparently.

Wasn't there talks about ending the lgpl version ? I thought I read somewhere that KDE devs were quite worried.

There are agreements with kde that prevent the Qt company from outright dropping free licenses: https://kde.org/community/whatiskde/kdefreeqtfoundation.php

As far as I can tell from that the LGPLv3 seems to be required under the current terms of the agreement.