At the moment, I have both versions on my computer. Can I remove the earlier version?
Thank you!
You can do, but I will keep Traktor Pro 3 as backup at least for a few month on my computer. But there is no need to in order to have Traktor Pro 4 work.
With each update, the previous version and its data remains intact, even if the updates are within a version, e.g. in Windows, they can be found in the documents folder.