If you pay a monthly fee you get 24/7 streaming and clips that you can share, whereas as without it you don't have 24/7 and a way to share and download the clips, also, with paid subscription, ($10/mo or $100 flat/year) it covers every device at one address, and you have access to clips up to 60 days later with sharing. Long story short, you can go based off just wifi, but you are limited to what you can and cannot do.