diff --git a/client/src/mobile/screens/admin/MAdmin.tsx b/client/src/mobile/screens/admin/MAdmin.tsx
index ff5c26d38..5f4923281 100644
--- a/client/src/mobile/screens/admin/MAdmin.tsx
+++ b/client/src/mobile/screens/admin/MAdmin.tsx
@@ -10,6 +10,7 @@ import {
   Database,
   FileText,
   Github,
+  HardDrive,
   Map,
   Plug,
   Puzzle,
@@ -39,6 +40,7 @@ import MAdminPackingTemplateManager from './MAdminPackingTemplateManager'
 import MAdminNotificationsSection from './MAdminNotificationsSection'
 import MAdminSettingsSection from './MAdminSettingsSection'
 import MAdminSheets from './MAdminSheets'
+import MAdminStoragePanel from './MAdminStoragePanel'
 import MAdminUsersSection from './MAdminUsersSection'
 import { MAdminButton } from './MAdminUi'
 
@@ -86,6 +88,7 @@ export default function MAdmin() {
     { id: 'settings', label: t('admin.tabs.settings'), icon: SettingsIcon },
     { id: 'addons', label: t('admin.tabs.addons'), icon: Blocks },
     { id: 'plugins', label: t('admin.tabs.plugins'), icon: Puzzle },
+    ...(managed ? [] : [{ id: 'storage', label: t('admin.tabs.storage'), icon: HardDrive }]),
     { id: 'notifications', label: t('admin.tabs.notifications'), icon: Bell },
     ...(mcpEnabled ? [{ id: 'mcp-tokens', label: t('admin.tabs.mcpTokens'), icon: Plug }] : []),
     // Same two the desktop list drops: releases and backup schedule belong to
@@ -238,6 +241,7 @@ export default function MAdmin() {
         />
       )}
       {activeTab === 'plugins' && <MAdminPluginsPanel />}
+      {activeTab === 'storage' && <MAdminStoragePanel />}
       {activeTab === 'mcp-tokens' && <MAdminMcpTokensPanel />}
       {activeTab === 'github' && <MAdminGitHubPanel isPrerelease={updateInfo?.is_prerelease ?? false} />}
       {activeTab === 'backup' && <MAdminBackupPanel />}
diff --git a/client/src/mobile/screens/admin/MAdminStoragePanel.tsx b/client/src/mobile/screens/admin/MAdminStoragePanel.tsx
new file mode 100644
index 000000000..c8ad9a9f2
--- /dev/null
+++ b/client/src/mobile/screens/admin/MAdminStoragePanel.tsx
@@ -0,0 +1,468 @@
+import React, { useState } from 'react'
+import { ChevronDown } from 'lucide-react'
+import {
+  STORAGE_BACKEND_TYPES,
+  STORAGE_BACKEND_TYPE_IDS,
+  STORAGE_CATEGORIES,
+  type StorageBackend,
+  type StorageBackendFieldDef,
+  type StorageBackendTypeId,
+  type StorageCategory,
+} from '@trek/shared'
+import { useTranslation } from '../../../i18n'
+import { useToast } from '../../../components/shared/Toast'
+import { relativeTime } from '../../../utils/relativeTime'
+import {
+  asWireBackend,
+  categoriesPointingAt,
+  hasPlaintextSecret,
+  mirrorsReferencing,
+  removeBackend,
+  upsertBackend,
+  type StateBackend,
+} from '../../../components/Admin/storage/storageModel'
+import { useStorageAdmin } from '../../../components/Admin/storage/useStorageAdmin'
+import MToggle from '../../components/MToggle'
+import MSetPickerSheet from '../settings/MSetPickerSheet'
+import MConfirmSheet from '../settings/MConfirmSheet'
+import { MSetSelectRow } from '../settings/MSettingsUi'
+import { MAdminButton, MAdminCard, MAdminCardHead, MAdminField, MAdminInput, MAdminSecretInput } from './MAdminUi'
+
+type FieldValues = Record<string, string | string[]>
+
+function valuesOf(backend: StorageBackend | null): FieldValues {
+  if (!backend) return {}
+  const values: FieldValues = {}
+  for (const [key, value] of Object.entries(backend.options)) {
+    values[key] = Array.isArray(value) ? value : String(value)
+  }
+  return values
+}
+
+/** Same behavior contract as the desktop BackendForm, rendered on the M* primitives. */
+function MBackendForm({
+  initial,
+  backendNames,
+  encryptionReady,
+  onCommit,
+  onCancel,
+}: {
+  initial: StorageBackend | null
+  backendNames: string[]
+  encryptionReady: boolean
+  onCommit: (backend: StorageBackend) => void
+  onCancel: () => void
+}): React.ReactElement {
+  const { t } = useTranslation()
+  const [type, setType] = useState<StorageBackendTypeId>(initial?.type ?? 'local')
+  const [name, setName] = useState(initial?.name ?? '')
+  const [values, setValues] = useState<FieldValues>(() => valuesOf(initial))
+  const [picker, setPicker] = useState<string | null>(null)
+
+  const fields = STORAGE_BACKEND_TYPES[type].fields as readonly StorageBackendFieldDef[]
+  const refOptions = backendNames.filter((candidate) => candidate !== name.trim())
+  const setValue = (key: string, value: string | string[]) => setValues((prev) => ({ ...prev, [key]: value }))
+
+  const filled = (field: StorageBackendFieldDef): boolean => {
+    const value = values[field.key]
+    if (field.kind === 'backend-ref-list') return Array.isArray(value) && value.length > 0
+    return typeof value === 'string' && value.trim() !== ''
+  }
+  const duplicate = initial === null && backendNames.includes(name.trim())
+  const blocked = hasPlaintextSecret({ type, options: values }) && !encryptionReady
+  const canApply = name.trim() !== '' && !duplicate && fields.every((f) => !f.required || filled(f))
+
+  const apply = () => {
+    const options: Record<string, unknown> = {}
+    for (const field of fields) {
+      const value = values[field.key]
+      if (field.kind === 'backend-ref-list') {
+        options[field.key] = Array.isArray(value) ? value : []
+        continue
+      }
+      const text = typeof value === 'string' ? value : ''
+      if (text === '' && !field.required) continue
+      options[field.key] = field.kind === 'number' ? Number(text) : text
+    }
+    onCommit({ name: name.trim(), type, options } as StorageBackend)
+  }
+
+  return (
+    <MAdminCard className="space-y-3">
+      <MAdminCardHead title={initial ? t('storage.form.editTitle') : t('storage.form.addTitle')} />
+      <MAdminField label={t('storage.form.name')}>
+        <MAdminInput value={name} onChange={(e) => setName(e.target.value)} spellCheck={false} autoComplete="off" />
+      </MAdminField>
+      {duplicate && (
+        <p role="alert" className="font-geist text-[0.625rem] text-m-muted">
+          {t('storage.form.duplicateName', { name: name.trim() })}
+        </p>
+      )}
+      {initial === null && (
+        <MAdminField label={t('storage.form.type')}>
+          <MSetSelectRow
+            label={t(`storage.type.${type}`)}
+            trailing={<ChevronDown size={14} className="text-m-faint" />}
+            onClick={() => setPicker('type')}
+          />
+          <MSetPickerSheet
+            open={picker === 'type'}
+            onClose={() => setPicker(null)}
+            title={t('storage.form.type')}
+            options={STORAGE_BACKEND_TYPE_IDS.map((id) => ({ value: id, label: t(`storage.type.${id}`) }))}
+            value={type}
+            onSelect={(next) => {
+              setType(next as StorageBackendTypeId)
+              setValues({})
+            }}
+          />
+        </MAdminField>
+      )}
+
+      {fields.map((field) => {
+        const value = values[field.key]
+        if (field.kind === 'backend-ref') {
+          const current = typeof value === 'string' ? value : ''
+          return (
+            <MAdminField key={field.key} label={t(field.labelKey)}>
+              <MSetSelectRow
+                label={current || t(field.labelKey)}
+                trailing={<ChevronDown size={14} className="text-m-faint" />}
+                onClick={() => setPicker(`field:${field.key}`)}
+              />
+              <MSetPickerSheet
+                open={picker === `field:${field.key}`}
+                onClose={() => setPicker(null)}
+                title={t(field.labelKey)}
+                options={refOptions.map((candidate) => ({ value: candidate, label: candidate }))}
+                value={current}
+                onSelect={(next) => setValue(field.key, next)}
+              />
+            </MAdminField>
+          )
+        }
+        if (field.kind === 'backend-ref-list') {
+          const selected = Array.isArray(value) ? value : []
+          return (
+            <MAdminField key={field.key} label={t(field.labelKey)}>
+              <div className="space-y-2">
+                {refOptions.map((candidate) => (
+                  <div key={candidate} className="flex items-center justify-between gap-2">
+                    <span className="text-[0.8125rem] font-semibold text-m-ink">{candidate}</span>
+                    <MToggle
+                      checked={selected.includes(candidate)}
+                      ariaLabel={candidate}
+                      onChange={(checked) =>
+                        setValue(
+                          field.key,
+                          checked ? [...selected, candidate] : selected.filter((existing) => existing !== candidate),
+                        )
+                      }
+                    />
+                  </div>
+                ))}
+              </div>
+            </MAdminField>
+          )
+        }
+        const text = typeof value === 'string' ? value : ''
+        const shared = {
+          value: text,
+          onChange: (e: React.ChangeEvent<HTMLInputElement>) => setValue(field.key, e.target.value),
+          placeholder: field.defaultValue !== undefined ? String(field.defaultValue) : '',
+          spellCheck: false,
+          autoComplete: 'off',
+        }
+        return (
+          <MAdminField key={field.key} label={t(field.labelKey)} hint={field.helpKey ? t(field.helpKey) : undefined}>
+            {field.kind === 'secret' ? (
+              <MAdminSecretInput {...shared} />
+            ) : (
+              <MAdminInput {...shared} type={field.kind === 'number' ? 'number' : 'text'} />
+            )}
+          </MAdminField>
+        )
+      })}
+
+      <div className="flex items-center gap-2">
+        {blocked ? (
+          <p role="alert" className="font-geist text-[0.625rem] leading-relaxed text-m-muted">
+            {t('storage.form.encryptionBanner')}
+          </p>
+        ) : (
+          <MAdminButton onClick={apply} disabled={!canApply}>
+            {t('storage.form.apply')}
+          </MAdminButton>
+        )}
+        <MAdminButton variant="ghost" onClick={onCancel}>
+          {t('storage.form.cancel')}
+        </MAdminButton>
+      </div>
+    </MAdminCard>
+  )
+}
+
+export default function MAdminStoragePanel(): React.ReactElement {
+  const { t, locale } = useTranslation()
+  const toast = useToast()
+  const admin = useStorageAdmin(t('common.error'))
+  const [editing, setEditing] = useState<{ initial: StorageBackend | null; originalName: string | null } | null>(null)
+  const [confirmRemove, setConfirmRemove] = useState<string | null>(null)
+  const [categoryPicker, setCategoryPicker] = useState<StorageCategory | null>(null)
+
+  if (admin.loading) {
+    return (
+      <MAdminCard>
+        <p className="font-geist text-[0.75rem] italic text-m-faint">{t('storage.loading')}</p>
+      </MAdminCard>
+    )
+  }
+  if (!admin.state || !admin.draft) {
+    return (
+      <MAdminCard>
+        <p role="alert" className="text-[0.8125rem] text-m-ink">{admin.loadError || t('common.error')}</p>
+      </MAdminCard>
+    )
+  }
+  const { state, draft } = admin
+
+  const draftNames = draft.backends.map((b) => b.name)
+  const backendNames = [...new Set([...state.backends.map((b) => b.name), ...draftNames])]
+  const stateByName = new Map(state.backends.map((b) => [b.name, b]))
+
+  interface Row {
+    name: string
+    type: StorageBackend['type']
+    source: 'built-in' | 'env' | 'settings'
+    backend: StorageBackend
+    categories: readonly string[]
+  }
+  const rows: Row[] = []
+  for (const b of state.backends) {
+    if (draftNames.includes(b.name)) continue
+    if (b.source === 'settings') continue
+    rows.push({ name: b.name, type: b.type, source: b.source, backend: asWireBackend(b), categories: b.categories })
+  }
+  for (const b of draft.backends) {
+    const inState = stateByName.get(b.name) as StateBackend | undefined
+    rows.push({
+      name: b.name,
+      type: b.type,
+      source: 'settings',
+      backend: b,
+      categories: inState?.categories ?? categoriesPointingAt(draft, b.name),
+    })
+  }
+
+  const commitBackend = (backend: StorageBackend) => {
+    const renamedFrom = editing?.originalName && editing.originalName !== backend.name ? editing.originalName : null
+    const base = renamedFrom ? removeBackend(draft, renamedFrom) : draft
+    admin.setDraft(upsertBackend(base, backend))
+    setEditing(null)
+  }
+
+  const removeMessage = (name: string): string => {
+    const assigned = categoriesPointingAt(draft, name)
+    const mirrors = mirrorsReferencing(draft, name)
+    return [
+      t('storage.remove.body', { name }),
+      assigned.length > 0 ? t('storage.remove.stillAssigned', { categories: assigned.join(', ') }) : '',
+      mirrors.length > 0 ? t('storage.remove.referencedBy', { backends: mirrors.join(', ') }) : '',
+    ]
+      .filter(Boolean)
+      .join(' ')
+  }
+
+  const setCategory = (category: StorageCategory, backendName: string) => {
+    const effective = state.categories[category]
+    const categories = { ...draft.categories }
+    if (effective.source === 'default' && backendName === effective.backend) {
+      delete categories[category]
+    } else {
+      categories[category] = backendName
+    }
+    admin.setDraft({ ...draft, categories })
+  }
+
+  const save = async () => {
+    if (await admin.save()) toast.success(t('storage.saved'))
+  }
+
+  return (
+    <div className="space-y-3">
+      <MAdminCard>
+        <MAdminCardHead title={t('storage.health.title')} />
+        {state.health.replicaFailures.length === 0 ? (
+          <p className="font-geist text-[0.75rem] text-m-faint">{t('storage.health.allClear')}</p>
+        ) : (
+          <div className="space-y-1">
+            {state.health.replicaFailures.map((failure) => (
+              <p key={`${failure.backend}-${failure.key}-${failure.at}`} className="text-[0.75rem] text-m-ink">
+                {t('storage.health.failureLine', {
+                  op: failure.op,
+                  key: failure.key,
+                  backend: failure.backend,
+                  error: failure.error,
+                })}{' '}
+                <span className="text-m-faint">· {relativeTime(failure.at, locale)}</span>
+              </p>
+            ))}
+          </div>
+        )}
+        {state.seedFilePresent && (
+          <p className="mt-1 font-geist text-[0.625rem] text-m-muted">{t('storage.health.seedFile')}</p>
+        )}
+      </MAdminCard>
+
+      <MAdminCard>
+        <MAdminCardHead title={t('storage.backends.title')} hint={t('storage.description')} />
+        <div className="space-y-2">
+          {rows.map((row) => {
+            const result = admin.testResults[row.name]
+            return (
+              <div
+                key={row.name}
+                data-testid={`m-storage-backend-${row.name}`}
+                className="rounded-xl border border-[color:var(--m-rowbr)] bg-[color:var(--m-sheet)] p-3"
+              >
+                <div className="flex flex-wrap items-center gap-2">
+                  <span className="text-[0.8125rem] font-bold text-m-ink">{row.name}</span>
+                  <span className="rounded-full border border-[color:var(--m-rowbr)] px-2 py-[1px] font-geist text-[0.625rem] text-m-muted">
+                    {t(`storage.type.${row.type}`)}
+                  </span>
+                  <span className="rounded-full border border-[color:var(--m-rowbr)] px-2 py-[1px] font-geist text-[0.625rem] text-m-muted">
+                    {t(`storage.source.${row.source}`)}
+                  </span>
+                </div>
+                <p className="mt-1 font-geist text-[0.625rem] text-m-muted">
+                  {row.categories.length > 0
+                    ? t('storage.backends.usedBy', { categories: row.categories.join(', ') })
+                    : t('storage.backends.unused')}
+                </p>
+                {row.source === 'env' && (
+                  <p className="mt-1 font-geist text-[0.625rem] text-m-muted">{t('storage.backends.envReadOnly')}</p>
+                )}
+                <div className="mt-2 flex gap-2">
+                  <MAdminButton variant="ghost" onClick={() => admin.test(row.backend)}>
+                    {t('storage.actions.test')}
+                  </MAdminButton>
+                  {row.source !== 'env' && (
+                    <MAdminButton variant="ghost" onClick={() => setEditing({ initial: row.backend, originalName: row.name })}>
+                      {t('storage.actions.edit')}
+                    </MAdminButton>
+                  )}
+                  {row.source === 'settings' && (
+                    <MAdminButton variant="danger" onClick={() => setConfirmRemove(row.name)}>
+                      {t('storage.actions.remove')}
+                    </MAdminButton>
+                  )}
+                </div>
+                {result === 'running' ? (
+                  <p className="mt-2 font-geist text-[0.625rem] text-m-muted">{t('storage.test.running')}</p>
+                ) : (
+                  result && (
+                    <div className="mt-2 space-y-0.5">
+                      <p className="text-[0.75rem] font-bold text-m-ink">
+                        {result.ok ? t('storage.test.ok') : t('storage.test.failed')}
+                      </p>
+                      {result.targets.map((target) => (
+                        <p key={target.name} className="font-geist text-[0.625rem] text-m-muted">
+                          {target.ok ? '✓' : '✗'} {target.name}
+                          {target.error ? ` — ${target.error}` : ''}
+                        </p>
+                      ))}
+                    </div>
+                  )
+                )}
+              </div>
+            )
+          })}
+        </div>
+        {editing === null && (
+          <div className="mt-3">
+            <MAdminButton onClick={() => setEditing({ initial: null, originalName: null })}>
+              {t('storage.backends.add')}
+            </MAdminButton>
+          </div>
+        )}
+      </MAdminCard>
+
+      {editing !== null && (
+        <MBackendForm
+          initial={editing.initial}
+          backendNames={backendNames}
+          encryptionReady={state.encryptionReady}
+          onCommit={commitBackend}
+          onCancel={() => setEditing(null)}
+        />
+      )}
+
+      <MAdminCard>
+        <MAdminCardHead title={t('storage.categories.title')} />
+        <div className="space-y-2">
+          {STORAGE_CATEGORIES.map((category) => {
+            const effective = state.categories[category]
+            const selected = draft.categories[category] ?? effective.backend
+            const changed = selected !== effective.backend
+            return (
+              <MAdminField key={category} label={t(`storage.category.${category}`)}>
+                <div data-testid={`m-storage-category-${category}`} className="contents">
+                  <MSetSelectRow
+                    label={
+                      effective.source === 'default' && selected === effective.backend
+                        ? `${selected} (${t('storage.categories.default')})`
+                        : selected
+                    }
+                    trailing={<ChevronDown size={14} className="text-m-faint" />}
+                    onClick={() => setCategoryPicker(category)}
+                  />
+                </div>
+                {changed && (
+                  <p role="alert" className="mt-1 font-geist text-[0.625rem] text-m-muted">
+                    {t('storage.categories.reassignWarning')}
+                  </p>
+                )}
+              </MAdminField>
+            )
+          })}
+        </div>
+        <MSetPickerSheet
+          open={categoryPicker !== null}
+          onClose={() => setCategoryPicker(null)}
+          title={categoryPicker ? t(`storage.category.${categoryPicker}`) : ''}
+          options={backendNames.map((name) => ({ value: name, label: name }))}
+          value={categoryPicker ? (draft.categories[categoryPicker] ?? state.categories[categoryPicker].backend) : ''}
+          onSelect={(name) => {
+            if (categoryPicker) setCategory(categoryPicker, name)
+          }}
+        />
+      </MAdminCard>
+
+      <div className="flex items-center gap-2">
+        <MAdminButton onClick={save} disabled={!admin.dirty} busy={admin.saving}>
+          {t('storage.save')}
+        </MAdminButton>
+        {admin.dirty && <span className="font-geist text-[0.625rem] text-m-muted">{t('storage.unsaved')}</span>}
+      </div>
+      {admin.saveError && (
+        <p role="alert" className="text-[0.8125rem] text-m-ink">
+          {admin.saveError}
+        </p>
+      )}
+
+      <MConfirmSheet
+        open={confirmRemove !== null}
+        onClose={() => setConfirmRemove(null)}
+        title={t('storage.remove.title')}
+        message={confirmRemove ? removeMessage(confirmRemove) : ''}
+        confirmLabel={t('storage.actions.remove')}
+        cancelLabel={t('storage.form.cancel')}
+        danger
+        onConfirm={() => {
+          if (confirmRemove) admin.setDraft(removeBackend(draft, confirmRemove))
+          setConfirmRemove(null)
+        }}
+      />
+    </div>
+  )
+}
diff --git a/client/tests/unit/mobile/admin/MAdmin.test.tsx b/client/tests/unit/mobile/admin/MAdmin.test.tsx
index 0193e5e8b..5a45f7f9d 100644
--- a/client/tests/unit/mobile/admin/MAdmin.test.tsx
+++ b/client/tests/unit/mobile/admin/MAdmin.test.tsx
@@ -55,6 +55,9 @@ vi.mock('../../../../src/mobile/screens/admin/MAdminGitHubPanel', () => ({
     <div data-testid="github-panel">{String(isPrerelease)}</div>
   ),
 }));
+vi.mock('../../../../src/mobile/screens/admin/MAdminStoragePanel', () => ({
+  default: () => <div data-testid="m-admin-storage-panel" />,
+}));
 
 // The addon manager is reduced to the two controls MAdmin wires itself.
 vi.mock('../../../../src/mobile/screens/admin/MAdminAddonManager', () => ({
@@ -213,6 +216,9 @@ describe('MAdmin', () => {
     await openSection('Plugins');
     expect(screen.getByTestId('plugins-panel')).toBeInTheDocument();
 
+    await openSection('Storage');
+    expect(screen.getByTestId('m-admin-storage-panel')).toBeInTheDocument();
+
     await openSection('Notifications');
     expect(screen.getByTestId('notifications-section')).toBeInTheDocument();
 
@@ -380,4 +386,11 @@ describe('MAdmin', () => {
     expect(root.className).not.toContain('h-full');
     expect(root.className).not.toContain('overflow-y-auto');
   });
+
+  it('FE-MOB-ADMIN-STOR-001: managed mode hides the Storage section', async () => {
+    seedStore(useAuthStore, { isAuthenticated: true, user: buildAdmin(), managed: true });
+    renderAdmin();
+    fireEvent.click(await screen.findByRole('button', { name: 'Administration' }));
+    expect(screen.queryByRole('button', { name: 'Storage' })).not.toBeInTheDocument();
+  });
 });
diff --git a/client/tests/unit/mobile/admin/MAdminStoragePanel.test.tsx b/client/tests/unit/mobile/admin/MAdminStoragePanel.test.tsx
new file mode 100644
index 000000000..ee354f3dd
--- /dev/null
+++ b/client/tests/unit/mobile/admin/MAdminStoragePanel.test.tsx
@@ -0,0 +1,93 @@
+import { http, HttpResponse } from 'msw';
+import { describe, expect, it } from 'vitest';
+import { MASKED_SETTING_VALUE, type StorageAdminState } from '@trek/shared';
+import { server } from '../../../helpers/msw/server';
+import { fireEvent, render, screen, waitFor, within } from '../../../helpers/render';
+import { ToastContainer } from '../../../../src/components/shared/Toast';
+import MAdminStoragePanel from '../../../../src/mobile/screens/admin/MAdminStoragePanel';
+
+function baseState(overrides: Partial<StorageAdminState> = {}): StorageAdminState {
+  return {
+    backends: [
+      { name: 'uploads-local', type: 'local', source: 'built-in', options: { root: '/data/uploads' }, categories: ['files', 'journey', 'covers', 'avatars', 'photos', 'photos-google', 'photos-trek'] },
+      { name: 'backups-local', type: 'local', source: 'built-in', options: { root: '/data/backups' }, categories: ['backups'] },
+      {
+        name: 'off-box', type: 's3', source: 'settings',
+        options: { endpoint: 'http://127.0.0.1:9000', bucket: 'trek', accessKeyId: 'ak', secretAccessKey: MASKED_SETTING_VALUE, region: 'us-east-1', keyPrefix: '', retries: 1, timeoutMs: 30000 },
+        categories: [],
+      },
+    ],
+    categories: {
+      files: { backend: 'uploads-local', source: 'default' },
+      journey: { backend: 'uploads-local', source: 'default' },
+      covers: { backend: 'uploads-local', source: 'default' },
+      avatars: { backend: 'uploads-local', source: 'default' },
+      places: { backend: 'uploads-local', source: 'default' },
+      photos: { backend: 'uploads-local', source: 'default' },
+      'photos-google': { backend: 'uploads-local', source: 'default' },
+      'photos-trek': { backend: 'uploads-local', source: 'default' },
+      backups: { backend: 'backups-local', source: 'default' },
+    },
+    health: { replicaFailures: [] },
+    encryptionReady: true,
+    seedFilePresent: false,
+    ...overrides,
+  };
+}
+
+async function renderPanel(state: StorageAdminState = baseState()) {
+  server.use(http.get('/api/admin/storage', () => HttpResponse.json(state)));
+  render(
+    <>
+      <ToastContainer />
+      <MAdminStoragePanel />
+    </>,
+  );
+  await waitFor(() => expect(screen.getByText('Backends')).toBeInTheDocument());
+}
+
+describe('MAdminStoragePanel', () => {
+  it('FE-MOB-MSTOR-001: renders every backend with type and source, env rows read-only', async () => {
+    await renderPanel();
+    const row = screen.getByTestId('m-storage-backend-off-box');
+    expect(within(row).getByText('S3')).toBeInTheDocument();
+    expect(within(row).getByText('Settings')).toBeInTheDocument();
+    expect(screen.getByText('No replica failures recorded.')).toBeInTheDocument();
+  });
+
+  it('FE-MOB-MSTOR-002: reassigning a category via the picker sheet warns and saves through one PUT', async () => {
+    let putBody: unknown;
+    await renderPanel();
+    server.use(
+      http.put('/api/admin/storage', async ({ request }) => {
+        putBody = await request.json();
+        return HttpResponse.json(baseState());
+      }),
+    );
+    fireEvent.click(within(screen.getByTestId('m-storage-category-files')).getByRole('button'));
+    fireEvent.click(screen.getByRole('button', { name: 'off-box' })); // picker option; selecting closes
+    expect(screen.getByText(/Existing objects do not move/)).toBeInTheDocument();
+    fireEvent.click(screen.getByRole('button', { name: 'Save changes' }));
+    await screen.findByText('Storage configuration saved');
+    expect((putBody as { categories: Record<string, string> }).categories.files).toBe('off-box');
+  });
+
+  it('FE-MOB-MSTOR-003: a typed plaintext secret without encryption replaces Apply with the ENCRYPTION_KEY banner', async () => {
+    await renderPanel(baseState({ encryptionReady: false }));
+    fireEvent.click(within(screen.getByTestId('m-storage-backend-off-box')).getByRole('button', { name: 'Edit' }));
+    fireEvent.change(screen.getByPlaceholderText('us-east-1'), { target: { value: 'eu-west-1' } }); // sanity: form is open
+    const secret = screen.getByDisplayValue(MASKED_SETTING_VALUE);
+    fireEvent.change(secret, { target: { value: 'sk-new' } });
+    expect(screen.queryByRole('button', { name: 'Apply' })).not.toBeInTheDocument();
+    expect(screen.getByRole('alert').textContent).toContain('ENCRYPTION_KEY');
+  });
+
+  it('FE-MOB-MSTOR-004: a 400 renders the server message verbatim', async () => {
+    await renderPanel();
+    server.use(http.put('/api/admin/storage', () => HttpResponse.json({ error: 'registry says no' }, { status: 400 })));
+    fireEvent.click(within(screen.getByTestId('m-storage-category-files')).getByRole('button'));
+    fireEvent.click(screen.getByRole('button', { name: 'off-box' }));
+    fireEvent.click(screen.getByRole('button', { name: 'Save changes' }));
+    expect(await screen.findByText('registry says no')).toBeInTheDocument();
+  });
+});