Where can I find the Fonn Construction app? Gabriela Wasylków April 12, 2019 11:09 Updated Follow Web 1. Go to www.app.fonn.io log into your account or sign up Android 1. Open Google play and search for Fonn, then install the app iPhone 1. Search for Fonn in the App Store and press install button Comments 0 comments Please sign in to leave a comment.