I purchased Premium today but I cannot see much difference. Where or when do I access or see all the new features. Voice messages for example. But not only that. It looks like it did before.
Todoist does look the same no matter what plan you are on, it just allows you to do more things. So for example. if you click on a task, then notes/comments. You should be able to add a note and attach a file.
You can see all Premium features here. http://todoist.com/premium