HOWSTUFFWORKS - Jan 28 - Backup Plan app is a new app created by the folks who created The Breakup Shop. The app will let users enter into a legally binding agreement to marry by an agreed-upon date, should they both still be single. Users create a profile and enter a marriage deadline date. They then rifle through local singles via a "Tinder-like interface." Should two people agree to serve as marriage backups, they establish the terms of the contract and sign it digitally.