Do searches of church blogs and facebook pages (example search "missionaries africa site:facebook.com"). Also, pitch it to some of the top christian/theology b

Do searches of church blogs and facebook pages (example search "missionaries africa site:facebook.com"). Also, pitch it to some of the top christian/theology blogs out there. Since your product is essentially free to setup/host and quite beneficial, I imagine you could get a few to post about it. Many of the missionaries I know meet with other nearby missionaries monthly or quarterly, so I think the word could spread if you were able to reach the right people.