diff --git a/src/routes/cloud/+page.svelte b/src/routes/cloud/+page.svelte
index e043b3a..c8e4d0b 100644
--- a/src/routes/cloud/+page.svelte
+++ b/src/routes/cloud/+page.svelte
@@ -2,21 +2,28 @@
   import { processFiles } from '$lib/upload';
   import Loader from '$lib/components/Loader.svelte';
   import { formatBytes, showSnackbar } from '$lib/util';
-  import { Card } from 'flowbite-svelte';
+  import { Button, Frame, Listgroup, ListgroupItem } from 'flowbite-svelte';
   import { onMount } from 'svelte';
   import { promptConfirmation } from '$lib/util';
   import { GoogleSolid } from 'flowbite-svelte-icons';
+  import { volumes } from '$lib/settings';
 
   const CLIENT_ID = import.meta.env.VITE_GDRIVE_CLIENT_ID;
   const API_KEY = import.meta.env.VITE_GDRIVE_API_KEY;
 
   const DISCOVERY_DOC = 'https://www.googleapis.com/discovery/v1/apis/drive/v3/rest';
   const SCOPES = 'https://www.googleapis.com/auth/drive';
+  const FILES_API_URL = 'https://www.googleapis.com/upload/drive/v3/files';
+
   const FOLDER_MIME_TYPE = 'application/vnd.google-apps.folder';
+  const READER_FOLDER = 'mokuro-reader';
+  const VOLUME_DATA_FILE = 'volume-data.json';
 
   let tokenClient: any;
   let zips: gapi.client.drive.File[];
   let loadingMessage = '';
+  let readerFolderId = '';
+  let volumeDataId = '';
 
   async function fetchZips(folderId: string) {
     const { result } = await gapi.client.drive.files.list({
@@ -78,19 +85,34 @@
 
     loadingMessage = 'Connecting to drive';
 
-    const { result } = await gapi.client.drive.files.list({
-      q: `mimeType='application/vnd.google-apps.folder' and name='MokuroReader'`,
+    const { result: readerFolderRes } = await gapi.client.drive.files.list({
+      q: `mimeType='application/vnd.google-apps.folder' and name='${READER_FOLDER}'`,
       fields: 'files(id)'
     });
 
-    if (result.files?.length === 0) {
-      await gapi.client.drive.files.create({
-        resource: { mimeType: FOLDER_MIME_TYPE, name: 'MokuroReader' },
+    if (readerFolderRes.files?.length === 0) {
+      const { result: createReaderFolderRes } = await gapi.client.drive.files.create({
+        resource: { mimeType: FOLDER_MIME_TYPE, name: READER_FOLDER },
         fields: 'id'
       });
-    } else {
-      zips = [...((await fetchZips(result.files?.[0]?.id || '')) || [])];
+
+      readerFolderId = createReaderFolderRes.id || '';
       loadingMessage = '';
+    } else {
+      const id = readerFolderRes.files?.[0]?.id || '';
+      zips = [...((await fetchZips(id)) || [])];
+
+      readerFolderId = id || '';
+      loadingMessage = '';
+    }
+
+    const { result: volumeDataRes } = await gapi.client.drive.files.list({
+      q: `'${readerFolderId}' in parents and name='${VOLUME_DATA_FILE}'`,
+      fields: 'files(id, name)'
+    });
+
+    if (volumeDataRes.files?.length !== 0) {
+      volumeDataId = volumeDataRes.files?.[0].id || '';
     }
 
     showSnackbar('Connected to Google Drive');
@@ -123,6 +145,62 @@
       callback: connectDrive
     });
   });
+
+  async function onUpload() {
+    const type = 'application/json';
+    const json = localStorage.getItem('volumes') || '';
+    const blob = new Blob([json], { type });
+
+    const metadata = {
+      mimeType: type,
+      name: VOLUME_DATA_FILE,
+      parents: [volumeDataId ? null : readerFolderId]
+    };
+
+    const { access_token } = gapi.auth.getToken();
+
+    const form = new FormData();
+
+    form.append('resource', new Blob([JSON.stringify(metadata)], { type }));
+    form.append('file', blob);
+
+    loadingMessage = 'Uploading volume data';
+
+    const res = await fetch(
+      `${FILES_API_URL}${volumeDataId ? `/${volumeDataId}` : ''}?uploadType=multipart`,
+      {
+        method: volumeDataId ? 'PATCH' : 'POST',
+        headers: new Headers({ Authorization: 'Bearer ' + access_token }),
+        body: form
+      }
+    );
+    volumeDataId = (await res.json()).id;
+
+    loadingMessage = '';
+
+    showSnackbar('Volume data uploaded');
+  }
+
+  async function onDownload() {
+    loadingMessage = 'Downloading volume data';
+
+    const { body } = await gapi.client.drive.files.get({
+      fileId: volumeDataId,
+      alt: 'media'
+    });
+
+    const downloaded = JSON.parse(body);
+
+    volumes.update((prev) => {
+      return {
+        ...prev,
+        ...downloaded
+      };
+    });
+
+    loadingMessage = '';
+    showSnackbar('Volume data downloaded');
+  }
 </script>
 
 <div class="p-10 h-[90svh]">
@@ -131,15 +209,50 @@
       {loadingMessage}
     </Loader>
   {:else if zips}
-    <div class="flex flex-col gap-5">
-      <h2 class="text-lg font-semibold text-center">Google drive:</h2>
-      <div class="flex gap-2 flex-wrap p-10 border rounded-lg border-slate-600 border-opacity-50">
-        {#each zips as zip}
-          <Card href="#" on:click={() => onClick(zip)}>
-            <h2 class="font-semibold">{zip.name}</h2>
-            <p>{formatBytes(parseInt(zip.size || '0'))}</p>
-          </Card>
-        {/each}
+    <div class="flex flex-col gap-2">
+      <div class="flex flex-col gap-5">
+        <h2 class="text-lg font-semibold text-center">Google Drive:</h2>
+        <div
+          class="flex gap-2 justify-center flex-wrap p-5 border rounded-lg border-slate-600 border-opacity-50"
+        >
+          {#if zips.length > 0}
+            <Listgroup active class="w-full">
+              {#each zips as zip}
+                <Frame
+                  on:click={() => onClick(zip)}
+                  rounded
+                  border
+                  class="divide-y divide-gray-200 dark:divide-gray-600"
+                >
+                  <ListgroupItem normalClass="py-4">
+                    <div class="flex flex-col gap-2">
+                      <h2 class="font-semibold">{zip.name}</h2>
+                      <p>{formatBytes(parseInt(zip.size || '0'))}</p>
+                    </div>
+                  </ListgroupItem>
+                </Frame>
+              {/each}
+            </Listgroup>
+          {:else}
+            <p class="text-center">
+              Add your zip files to the <span class="text-primary-700">{READER_FOLDER}</span> folder
+              in your Google Drive.
+            </p>
+          {/if}
+        </div>
+      </div>
+      <div class="flex gap-2">
+        <Button color="dark" on:click={() => promptConfirmation('Upload volume data?', onUpload)}>
+          Upload volume data
+        </Button>
+        {#if volumeDataId}
+          <Button
+            color="alternative"
+            on:click={() => promptConfirmation('Download and overwrite volume data?', onDownload)}
+          >
+            Download volume data
+          </Button>
+        {/if}
       </div>
     </div>
   {:else}
@@ -147,7 +260,7 @@
       class="w-full border rounded-lg border-slate-600 p-10 border-opacity-50 hover:bg-slate-800"
       on:click={signIn}
     >
-      <div class="flex gap-2 items-center justify-center">
+      <div class="flex sm:flex-row flex-col gap-2 items-center justify-center">
         <GoogleSolid size="lg" />
         <h2 class="text-lg">Connect to Google Drive</h2>
       </div>