Urtext is local first, meaning it expects files present locally on each device without an internet connection. Interaction with cloud services is beyond its intended scope.

Desktop

Using a desktop implementation (currently Sublime Urtext), files will persist across many devices on a number of popular cloud services without issue.

iOS

Though not explicit in user-facing documentation, cloud-based file applications for iOS such as Files do not retain local copies of all files at all times. They remove less frequently accessed files, maintaining links to their locations in cloud storage that must be manually downloaded when needed. Though intended to optimize device storage, this feature presents a problem for local-first applications.

Several third party solutions have been tested, with no complete solution identified to date.

Setting up persistent local copies of Urtext files in Pythonista on iOS