I've just come across the most adorable wedding app which also serves as the ultimate guest-concierge service~
APPY COUPLE!

Appy Couple is the most magical and stylish way to create and publish your own mobile wedding app (and website). It's private. It's social It's easy. Couples can ensure that guests have everything they could possibly need at their fingertips and stay socially connected—no more patched together solutions of DIY websites, photo sharing apps, social networks and emails: Appy Couple connects the dots and puts it all-together.

So fun~ Enjoy! xoxo