Creating PDF Annotation Layers

Instant sync and collaboration is available when using the Web SDK with Document Engine in server-backed operational mode.

An Instant layer is a container for annotations on a specific PDF document. For everyone with write access to this container, the layer provides an editing context for the annotations it contains. People who only have read access to a layer may still download and view the document with all the annotations in the container. However, they won’t be able to make any changes to those annotations.

Instant layers are particularly useful for implementing review workflows where several parties are invited to provide feedback on a document independent of one another. One example would be student-teacher workflows, where all students independently annotate the same PDF document, while the teacher can annotate each student’s private layer, which only the student can see.

Because all layers with the same document identifier can share the same PDF file, adding a layer is cheap in terms of storage and bandwidth — on the clients as well as on the server.

For more information about layers, see our Instant Layers API reference for Document Engine.