For smartphones based on the IOS or Android operating system, the Once app is available. It's a handy app with a well-designed interface. For users' convenience, the desktop site and the Once app have absolutely identical functions, which simplifies the use and access to all the features. In terms of technical implementation, this is one of the best apps among similar dating sites. The design is concise. The app is free to download, but there will be the same restrictions when using it as on the website.