COMTiles (github.com/mactrem/com-tiles) is a streamable and read optimized file archive for hosting map tiles at global scale on a cloud object storage. Currently most geospatial data formats (like MBTiles or Shapefiles) were developed only with the POSIX filesystem access in mind. COMTiles in contrast is designed to be hosted on a cloud object storage like AWS S3 or Azure Blob Storage without the need for a database or server on the backend side. The map tiles of a COMTiles archive can be accessed directly from a browser via HTTP range requests. COMTiles are already successfully used in some projects to significantly reduce the hosting costs and simplify the handling of large tilesets in the cloud. Structure of the talk: - Basic concepts of COMTiles like the structure of the streamable index table (pyramids vs space-filling curves vs fragments) - Comparison of COMTiles to existing cloud native geospatial formats regarding the visualization of large datasets in the browser - Advantages of using a streamable archive format like COMTiles over directly hosting the map tiles in the cloud