Image gallery with backend, poor performance

Thanks for the feedback! As Здравко said, there may some ways to optimize your call pattern, but it would very much depend on your particular scenario, and it sounds like you have certain design constraints to accommodate. As for the Dropbox API itself, you're already using the right endpoints. The /2/files/list_folder[/continue] endpoints are the right way to list the contents of a folder; /2/files/get_thumbnail_batch is the best way to retrieve multiple thumbnails at once; and /2/files/get_temporary_link is the right way to get a direct link for a file, and there isn't a batch version of that available. There isn't any way to just speed up these endpoints, but I'll pass this along as a feature request for various performance/batching improvements. I can't promise if or when any of these might be implemented though.