diff --git a/package-lock.json b/package-lock.json
index 7863f284c..8fab84da7 100644
--- a/package-lock.json
+++ b/package-lock.json
@@ -21769,6 +21769,18 @@
         "expo": "*"
       }
     },
+    "node_modules/expo-image-manipulator": {
+      "version": "14.0.8",
+      "resolved": "https://registry.npmjs.org/expo-image-manipulator/-/expo-image-manipulator-14.0.8.tgz",
+      "integrity": "sha512-sXsXjm7rIxLWZe0j2A41J/Ph53PpFJRdyzJ3EQ/qetxLUvS2m3K1sP5xy37px43qCf0l79N/i6XgFgenFV36/Q==",
+      "license": "MIT",
+      "dependencies": {
+        "expo-image-loader": "~6.0.0"
+      },
+      "peerDependencies": {
+        "expo": "*"
+      }
+    },
     "node_modules/expo-image-picker": {
       "version": "17.0.10",
       "resolved": "https://registry.npmjs.org/expo-image-picker/-/expo-image-picker-17.0.10.tgz",
@@ -38886,6 +38898,7 @@
         "expo-file-system": "~19.0.17",
         "expo-haptics": "~15.0.7",
         "expo-image": "~3.0.10",
+        "expo-image-manipulator": "~14.0.8",
         "expo-image-picker": "^17.0.8",
         "expo-keep-awake": "^15.0.7",
         "expo-linking": "~8.0.8",
diff --git a/packages/app/package.json b/packages/app/package.json
index 86bb1910c..4284af22f 100644
--- a/packages/app/package.json
+++ b/packages/app/package.json
@@ -63,6 +63,7 @@
     "expo-file-system": "~19.0.17",
     "expo-haptics": "~15.0.7",
     "expo-image": "~3.0.10",
+    "expo-image-manipulator": "~14.0.8",
     "expo-image-picker": "^17.0.8",
     "expo-keep-awake": "^15.0.7",
     "expo-linking": "~8.0.8",
diff --git a/packages/app/src/hooks/image-attachment-picker.native.test.ts b/packages/app/src/hooks/image-attachment-picker.native.test.ts
new file mode 100644
index 000000000..fd1fa52a1
--- /dev/null
+++ b/packages/app/src/hooks/image-attachment-picker.native.test.ts
@@ -0,0 +1,75 @@
+import { describe, expect, it, vi } from "vitest";
+
+vi.mock("expo-image-manipulator", () => ({
+  SaveFormat: { PNG: "png" },
+  ImageManipulator: {
+    manipulate: (_source: string) => ({
+      async renderAsync() {
+        return {
+          release() {},
+          async saveAsync(options: { format?: string }) {
+            return {
+              uri:
+                options.format === "png"
+                  ? "file:///cache/ImageManipulator/safe-picked.png"
+                  : "file:///cache/ImageManipulator/unsafe-picked.jpg",
+              width: 100,
+              height: 100,
+            };
+          },
+        };
+      },
+      release() {},
+    }),
+  },
+}));
+
+import { normalizePickedImageAssets } from "./image-attachment-picker.native";
+
+describe("native image attachment picker", () => {
+  it("preserves native picked JPEG and PNG attachment inputs", async () => {
+    const result = await normalizePickedImageAssets([
+      {
+        uri: "file:///photos/IMG_0001.JPG",
+        mimeType: "image/jpeg",
+        fileName: "picked.jpeg",
+      },
+      {
+        uri: "file:///photos/screenshot.png",
+        mimeType: "image/png",
+        fileName: "screenshot.png",
+      },
+    ]);
+
+    expect(result).toEqual([
+      {
+        source: { kind: "file_uri", uri: "file:///photos/IMG_0001.JPG" },
+        mimeType: "image/jpeg",
+        fileName: "picked.jpg",
+      },
+      {
+        source: { kind: "file_uri", uri: "file:///photos/screenshot.png" },
+        mimeType: "image/png",
+        fileName: "screenshot.png",
+      },
+    ]);
+  });
+
+  it("turns a native picked HEIC-like asset into a PNG attachment input", async () => {
+    const result = await normalizePickedImageAssets([
+      {
+        uri: "file:///photos/IMG_0001.HEIC",
+        mimeType: "image/png",
+        fileName: "picked.png",
+      },
+    ]);
+
+    expect(result).toEqual([
+      {
+        source: { kind: "file_uri", uri: "file:///cache/ImageManipulator/safe-picked.png" },
+        mimeType: "image/png",
+        fileName: "picked.png",
+      },
+    ]);
+  });
+});
diff --git a/packages/app/src/hooks/image-attachment-picker.native.ts b/packages/app/src/hooks/image-attachment-picker.native.ts
new file mode 100644
index 000000000..23d9bb351
--- /dev/null
+++ b/packages/app/src/hooks/image-attachment-picker.native.ts
@@ -0,0 +1,129 @@
+import { ImageManipulator, SaveFormat } from "expo-image-manipulator";
+
+export type PickedImageSource = { kind: "file_uri"; uri: string } | { kind: "blob"; blob: Blob };
+
+export interface PickedImageAttachmentInput {
+  source: PickedImageSource;
+  mimeType?: string | null;
+  fileName?: string | null;
+}
+
+export interface ExpoImagePickerAssetLike {
+  uri: string;
+  mimeType?: string | null;
+  fileName?: string | null;
+  file?: File | null;
+}
+
+interface SupportedPickedImageFormat {
+  mimeType: "image/jpeg" | "image/png";
+  extension: "jpg" | "png";
+}
+
+const JPEG_FORMAT: SupportedPickedImageFormat = {
+  mimeType: "image/jpeg",
+  extension: "jpg",
+};
+
+const PNG_FORMAT: SupportedPickedImageFormat = {
+  mimeType: "image/png",
+  extension: "png",
+};
+
+function extensionFromPath(path: string | null | undefined): string | null {
+  const match = path?.match(/\.([a-z0-9]+)(?:[?#].*)?$/i);
+  return match?.[1]?.toLowerCase() ?? null;
+}
+
+function supportedFormatForExtension(extension: string | null): SupportedPickedImageFormat | null {
+  if (extension === "jpg" || extension === "jpeg") {
+    return JPEG_FORMAT;
+  }
+  if (extension === "png") {
+    return PNG_FORMAT;
+  }
+  return null;
+}
+
+function supportedFormatForMimeType(
+  mimeType: string | null | undefined,
+): SupportedPickedImageFormat | null {
+  const normalizedMimeType = mimeType?.toLowerCase();
+  if (normalizedMimeType === "image/jpeg" || normalizedMimeType === "image/jpg") {
+    return JPEG_FORMAT;
+  }
+  if (normalizedMimeType === "image/png") {
+    return PNG_FORMAT;
+  }
+  return null;
+}
+
+function pickedAssetSupportedFormat(
+  asset: ExpoImagePickerAssetLike,
+): SupportedPickedImageFormat | null {
+  const uriExtension = extensionFromPath(asset.uri);
+  if (uriExtension) {
+    return supportedFormatForExtension(uriExtension);
+  }
+
+  return (
+    supportedFormatForExtension(extensionFromPath(asset.fileName)) ??
+    supportedFormatForMimeType(asset.mimeType)
+  );
+}
+
+function replaceFileExtension(
+  fileName: string | null | undefined,
+  extension: SupportedPickedImageFormat["extension"],
+): string | null {
+  if (!fileName) {
+    return null;
+  }
+
+  return fileName.replace(/\.[^./\\]+$/, "") + `.${extension}`;
+}
+
+async function exportPickedImageAsPng(uri: string): Promise<string> {
+  const context = ImageManipulator.manipulate(uri);
+  let image: Awaited<ReturnType<typeof context.renderAsync>> | null = null;
+
+  try {
+    image = await context.renderAsync();
+    const result = await image.saveAsync({
+      format: SaveFormat.PNG,
+    });
+    return result.uri;
+  } finally {
+    image?.release();
+    context.release();
+  }
+}
+
+export async function normalizePickedImageAssets(
+  assets: readonly ExpoImagePickerAssetLike[],
+): Promise<PickedImageAttachmentInput[]> {
+  return await Promise.all(
+    assets.map(async (asset) => {
+      const supportedFormat = pickedAssetSupportedFormat(asset);
+      if (supportedFormat) {
+        return {
+          source: { kind: "file_uri", uri: asset.uri },
+          mimeType: supportedFormat.mimeType,
+          fileName: replaceFileExtension(asset.fileName, supportedFormat.extension),
+        };
+      }
+
+      const convertedUri = await exportPickedImageAsPng(asset.uri);
+
+      return {
+        source: { kind: "file_uri", uri: convertedUri },
+        mimeType: PNG_FORMAT.mimeType,
+        fileName: replaceFileExtension(asset.fileName, PNG_FORMAT.extension),
+      };
+    }),
+  );
+}
+
+export async function openImagePathsWithDesktopDialog(): Promise<string[]> {
+  throw new Error("Desktop dialog API is not available on native.");
+}