Position statement for W3C Workshop on Web Games Author: Yuki Kuwabara (Drecom Co., Ltd.) Background Drecom develops HTML5 game platform called Enza*. Enza provides HTML5 games that mainly targeted to browsers on mobile devices (iOS and Android). At the point of April, 1st, 2019, five titles are published on Enza. Those games are updated for long term with new features, characters and stories, so it is unlike casual games. In Japanese mobile game market, these kind of games are majority and most of the mobile game users are used to play that kind of games. Topic The games described as above usually have to handle tons of resources, such as textures and sounds. Most of the problems that I experienced are comes from the mismatch of this game design and web specification. In HTML5, there are some ways to store donwloaded resources but every solution is not the perfect one. Using local file storage is the most easiest way to solve this problem. Indexed DB provides the interface to storing resources to local storrage but it has problems with performance and data type. Expectation Through the HTML5 game development, I studied that controling caches via http header is the good way for keeping performance, and it can be retrieved as almost raw data. But it is very different from handling local storage, so I still need further investigation of cache controlling system that can be operated easily. On the other hand, FileSystem API may be helpful specification, but it has a sensitive matter about privacy. To clarifiy the current status of this API and privacy policy would be helpful to design future web friendly resource handling. * Reference: Enza - http://enza.fun mobile HTML5 game platform available only in Japan. Quality and volume of enza games can be seen in user’s walkthrough movies Idol Master https://www.youtube.com/watch?v=0yxCF85QqMg Dragon Ball https://www.youtube.com/watch?v=NgD8e-YiQG4