As Instagram continues its meteoric rise, an ecosystem of third-party services is developing around it. Postagram is one such service by Xobni co-founder Matt Brezina and his new company Sincerely. It lets you easy send physical prints of your Instagram photos as postcards with personalized messages. The photo itself pops out of the postcard as a glossy 300-dpi print. Postagram is available as a free download in the App Store, while each postcard costs $1 and arrives in 2-5 days.