Sure, just copy/paste the template below. Make sure to fill in your own app code.
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Hey Everyone -
[INSERT YOUR FIANCE'S NAME HERE] and I are super excited for the wedding and we hope that you are too! We wanted to share a little "added element" of our wedding that we hope you will all be a part of. All you need to have is an iPhone or Android.
We did not hire a videographer for our wedding. Instead, we heard of the company WeddingMix and decided to try it out. Basically, we've paid this company to make us a custom app that we can share with you. If you download it onto your phone and take videos during any part of our wedding weekend, they will collect them for us. You can upload all your photos too!
Simply go to the App store or Google Play - it's a free app. Any iOS or Android with video can include clips into our project for free.
The password to log into our wedding is [project_app_code].
Feel free to take videos as much or as little as you want of ANYTHING (seriously, anything) you want. As much as we'd love to capture all of the "standard" wedding moments, we'd also love you guys to video your ride down, getting ready, any well wishes, etc. Have fun with it!
Thank you all so much for being part of our day. We can't wait to celebrate with everyone!
[YOUR NAMES HERE]