---
title: "Create PDF annotation layers in Flutter"
canonical_url: "https://www.nutrient.io/guides/flutter/instant-synchronization/instant-layers/"
md_url: "https://www.nutrient.io/guides/flutter/instant-synchronization/instant-layers.md"
last_updated: "2026-06-09T10:25:14.448Z"
description: "Learn how to create PDF annotation layers in Flutter for efficient collaboration and feedback sharing with your team."
---

# Create PDF annotation layers in Flutter

## What is an Instant layer?

An Instant layer represents a set of document changes, such as annotations, bookmarks, form fields, and digital signatures. Users with write access can edit the layer, while those with read access can only view it.

## What it’s best for

Layers are ideal for independent review workflows where multiple parties need to annotate or modify the same document separately. Common use cases include:

- **Student-teacher workflows** — Students annotate the same PDF independently, while teachers provide private feedback on each student’s layer

- **Multi-reviewer processes** — Different reviewers provide feedback without seeing each other’s comments

## Benefits

- **Low storage cost** —  Layers on the same document identifier share access to the same source file, eliminating the need to reupload, while keeping each layer’s content isolated

- **Minimal bandwidth** — Adding layers doesn’t require transferring the document again

- **Scalable** — It’s inexpensive to add multiple layers on clients and servers

For more information about layers, refer to the [Instant layers](https://www.nutrient.io/api/reference/document-engine/upstream/#tag/Layers) guide.
---

## Related pages

- [Sync PDF annotations in Flutter apps](/guides/flutter/instant-synchronization/annotation-sync.md)
- [Client authentication in Nutrient Instant](/guides/flutter/instant-synchronization/authentication.md)
- [Instant sync and document state in Flutter](/guides/flutter/instant-synchronization/document-state.md)
- [Adding Instant comments to PDFs in Flutter](/guides/flutter/instant-synchronization/comments.md)
- [Integrating real-time collaboration into your Flutter application](/guides/flutter/instant-synchronization/get-started.md)
- [PDF collaboration library for Flutter](/guides/flutter/instant-synchronization.md)
- [NutrientInstantView widget](/guides/flutter/instant-synchronization/instant-view.md)
- [Offline PDF annotations with automatic sync](/guides/flutter/instant-synchronization/offline-support.md)
- [Nutrient Instant usage](/guides/flutter/instant-synchronization/usage.md)