Sales tax for paid apps is somewhat well defined depending on state tax code, things like downloadable or boxed software seem to be covered, and most states will require a sales tax for sold / downloadable apps.
However a grey area is Freemium model apps that rely on in app purchases.
Lets take the simplest scenario as an example, where the app shows Ads and the user can pay $0.99 to remove ads via in app purchase. Now there wasn't any software exchanged at that point, as in no additional screens or in-app / in-game items were added or unlocked.
In this scenario where just ads are removed, is there a need to charge sales tax? Is that considered a software sale ?
This is for US, NY.