What if you let users sign up and use the site for 1 month free? They would be more invested in the site after a month and be more likely to part with some money. I would guess that you would make more money with one month free + 5 dollars for the rest of the year vs 5 dollars up front.

I really like the dropbox model of subscriptions. I would never had paid money when I signed up for dropbox, but now I'm right at my free limit. They have me in a win/win for them - I either pay to increase my storage or refer friends. For 365.io I think users would really get the concept after they see their "free" 30 pictures.

Great job on the design.