I'd like to offer a different perspective.
Looking at your home page, you sort of emphasize Facebook. So, I assume you target Facebook users. It's the largest social network on the planet. You shoudn't have any problem finding potential customers.
Thus I wonder: Why are you trying to get more exposure elsewhere? When you say, you have problems getting the "foot into the door", it seems your past activities were not as successful as you imagined.
So, what is the real problem?
I haven't researched your activities on Facebook, but maybe, your prospects simply can't related to your product. Remember what Harvard Business School's marketing professor Theodore Levitt said: “People don’t want to buy a quarter-inch drill. They want a quarter-inch hole!”
Maybe, your problem is not the lack of exposure but presentation. You're selling a photobook creation app while your customers are more interested to remember their bachelor party, their university degree, their holidays, their wedding, the birth of their new child, its first day in school, etc. They want to have easy, inexpensive, personal presents for family members and relatives.
Your homepage is about technology and features. It should be about benefit.
Your homepage also doesn't look trustworthy. It's selling too hard. It also doesn't address possible objections: Your testimonial box is below the fold and hardly noticeable, your demo button is too small and hard to find, and the 'demo' appears to be a video -- and bad one, unfortunately. There seems to be no free trial.
Fix your homepage, first. Then, you may also get more exposure because people will understand what the benefit is.
Hope that helps.