The difference is that you can record without any time limited and export your edited audios without any restriction in the full version while you can record voice shorter than 1 minute and can’t export your edited recording in the free version.
When you try to record voice longer than 1 minute or export your edited recording, a window will pop-up to tell you that you will need to update your purchase plan for this feature. We highly recommend you upgrade your plan and enjoy all functions of VoxBox.