I just noticed on the Shutterfly page that they are offering free 4"x6" and 4"x4" prints when ordering with their app.
Link to Shutterfly page with links to the apps.
Its a limited time promotion and they don't say exactly when it expires.
However the catch is that they do charge $1.99 shipping. Of course if you order say 50 or 100 prints that makes it pretty economical per print.
You can also get unlimited free photo storage at Shutterfly.
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