diff --git a/backend/aopp_approval_external_test.go b/backend/aopp_approval_external_test.go
new file mode 100644
index 000000000..58d8dce33
--- /dev/null
+++ b/backend/aopp_approval_external_test.go
@@ -0,0 +1,236 @@
+
+
+
+
+
+
+
+
+
+
+
+
+
+
+package backend_test
+
+import (
+	"fmt"
+	"net/http"
+	"net/http/httptest"
+	"net/url"
+	"testing"
+
+	"github.com/digitalbitbox/bitbox-wallet-app/backend"
+	"github.com/digitalbitbox/bitbox-wallet-app/backend/arguments"
+	"github.com/digitalbitbox/bitbox-wallet-app/backend/coins/btc"
+	"github.com/digitalbitbox/bitbox-wallet-app/backend/coins/btc/types"
+	coinpkg "github.com/digitalbitbox/bitbox-wallet-app/backend/coins/coin"
+	"github.com/digitalbitbox/bitbox-wallet-app/backend/devices/device"
+	deviceevent "github.com/digitalbitbox/bitbox-wallet-app/backend/devices/device/event"
+	"github.com/digitalbitbox/bitbox-wallet-app/backend/devices/usb"
+	"github.com/digitalbitbox/bitbox-wallet-app/backend/handlers"
+	"github.com/digitalbitbox/bitbox-wallet-app/backend/keystore"
+	keystoremock "github.com/digitalbitbox/bitbox-wallet-app/backend/keystore/mocks"
+	"github.com/digitalbitbox/bitbox-wallet-app/backend/keystore/software"
+	"github.com/digitalbitbox/bitbox-wallet-app/backend/signing"
+	"github.com/digitalbitbox/bitbox-wallet-app/util/observable"
+	"github.com/digitalbitbox/bitbox-wallet-app/util/test"
+	"github.com/stretchr/testify/require"
+)
+
+type aoppTestEnv struct{}
+
+func (aoppTestEnv) NotifyUser(string)             {}
+func (aoppTestEnv) DeviceInfos() []usb.DeviceInfo { return nil }
+func (aoppTestEnv) SystemOpen(string) error       { return nil }
+func (aoppTestEnv) UsingMobileData() bool         { return false }
+func (aoppTestEnv) NativeLocale() string          { return "en" }
+
+type aoppTestDevice struct {
+	observable.Implementation
+	keystore keystore.Keystore
+	onEvent  func(deviceevent.Event, interface{})
+}
+
+func (d *aoppTestDevice) Init(bool) error {
+	d.onEvent(deviceevent.EventKeystoreAvailable, nil)
+	return nil
+}
+
+func (d *aoppTestDevice) ProductName() string { return "test-device" }
+func (d *aoppTestDevice) Identifier() string  { return "aopp-test-device" }
+func (d *aoppTestDevice) Keystore() keystore.Keystore {
+	return d.keystore
+}
+func (d *aoppTestDevice) SetOnEvent(f func(deviceevent.Event, interface{})) { d.onEvent = f }
+func (d *aoppTestDevice) Close()                                            {}
+
+func newAOPPTestBackend(t *testing.T) *backend.Backend {
+	t.Helper()
+	b, err := backend.NewBackend(
+		arguments.NewArguments(
+			test.TstTempDir("aopp-approval"),
+			false, false,
+			false, false,
+			&types.GapLimits{Receive: 20, Change: 6}),
+		aoppTestEnv{},
+	)
+	require.NoError(t, err)
+	b.RatesUpdater().SetCoingeckoURL("unused")
+	b.OnDeviceInit(func(device.Interface) {})
+	b.OnDeviceUninit(func(string) {})
+	return b
+}
+
+func registerAOPPSigningKeystore(t *testing.T, b *backend.Backend) {
+	t.Helper()
+	keystoreHelper := software.NewKeystoreFromPIN("0000")
+	ks := &keystoremock.KeystoreMock{
+		RootFingerprintFunc: func() ([]byte, error) {
+			return []byte{0x55, 0x55, 0x55, 0x55}, nil
+		},
+		SupportsAccountFunc: func(coin coinpkg.Coin, meta interface{}) bool {
+			switch coin.(type) {
+			case *btc.Coin:
+				scriptType := meta.(signing.ScriptType)
+				return scriptType != signing.ScriptTypeP2PKH
+			default:
+				return true
+			}
+		},
+		SupportsUnifiedAccountsFunc: func() bool {
+			return true
+		},
+		SupportsMultipleAccountsFunc: func() bool {
+			return true
+		},
+		CanSignMessageFunc: func(coinpkg.Code) bool {
+			return true
+		},
+		ExtendedPublicKeyFunc: keystoreHelper.ExtendedPublicKey,
+	}
+	require.NoError(t, b.Register(&aoppTestDevice{keystore: ks}))
+}
+
+func defaultAOPPParams() url.Values {
+	params := url.Values{}
+	params.Set("v", "0")
+	params.Set("msg", "message to be signed")
+	params.Set("format", "any")
+	params.Set("asset", "btc")
+	params.Set("callback", "http://localhost/aopp/")
+	return params
+}
+
+func postAOPPRoute(t *testing.T, b *backend.Backend, path string) {
+	t.Helper()
+	h := handlers.NewHandlers(b, handlers.NewConnectionData(0, ""))
+	request := httptest.NewRequest(http.MethodPost, path, nil)
+	response := httptest.NewRecorder()
+	h.Router.ServeHTTP(response, request)
+	require.Equal(t, http.StatusOK, response.Code)
+}
+
+func currentAOPPState(b *backend.Backend) string {
+	return fmt.Sprint(b.AOPP().State)
+}
+
+func currentAOPPErrorCode(b *backend.Backend) string {
+	return fmt.Sprint(b.AOPP().ErrorCode)
+}
+
+func TestAOPPSuccess(t *testing.T) {
+	t.Run("user-approval-before-account-selection", func(t *testing.T) {
+		b := newAOPPTestBackend(t)
+		defer b.Close()
+
+		params := defaultAOPPParams()
+		params.Set("callback", "https://approval-gate.example.org/callback")
+		registerAOPPSigningKeystore(t, b)
+		b.HandleURI("aopp:?" + params.Encode())
+
+		require.Equal(t, "user-approval", currentAOPPState(b))
+		require.NotEqual(t, "choosing-account", currentAOPPState(b))
+		require.Equal(t, "approval-gate.example.org", b.AOPP().CallbackHost)
+	})
+
+	t.Run("approve-continues-flow", func(t *testing.T) {
+		b := newAOPPTestBackend(t)
+		defer b.Close()
+
+		params := defaultAOPPParams()
+		params.Set("callback", "https://approval-continues.example.org/callback")
+		registerAOPPSigningKeystore(t, b)
+		b.HandleURI("aopp:?" + params.Encode())
+		require.Equal(t, "user-approval", currentAOPPState(b))
+
+		postAOPPRoute(t, b, "/api/aopp/approve")
+
+		require.Equal(t, "choosing-account", currentAOPPState(b))
+		require.NotEmpty(t, b.AOPP().Accounts)
+	})
+
+	t.Run("approve-noops-outside-approval", func(t *testing.T) {
+		b := newAOPPTestBackend(t)
+		defer b.Close()
+		require.Equal(t, "inactive", currentAOPPState(b))
+
+		postAOPPRoute(t, b, "/api/aopp/approve")
+
+		require.Equal(t, "inactive", currentAOPPState(b))
+	})
+
+	t.Run("approval-keystore-disconnect", func(t *testing.T) {
+		b := newAOPPTestBackend(t)
+		defer b.Close()
+
+		params := defaultAOPPParams()
+		params.Set("callback", "https://approval-disconnect.example.org/callback")
+		registerAOPPSigningKeystore(t, b)
+		b.HandleURI("aopp:?" + params.Encode())
+		require.Equal(t, "user-approval", currentAOPPState(b))
+		b.DeregisterKeystore()
+
+		postAOPPRoute(t, b, "/api/aopp/approve")
+
+		require.Equal(t, "awaiting-keystore", currentAOPPState(b))
+		require.NotEqual(t, "choosing-account", currentAOPPState(b))
+	})
+
+	t.Run("cancel-from-approval-stops-before-account-selection", func(t *testing.T) {
+		b := newAOPPTestBackend(t)
+		defer b.Close()
+
+		params := defaultAOPPParams()
+		params.Set("callback", "https://approval-cancel.example.org/callback")
+		registerAOPPSigningKeystore(t, b)
+		b.HandleURI("aopp:?" + params.Encode())
+		require.Equal(t, "user-approval", currentAOPPState(b))
+
+		postAOPPRoute(t, b, "/api/aopp/cancel")
+
+		require.Equal(t, "inactive", currentAOPPState(b))
+		require.NotEqual(t, "choosing-account", currentAOPPState(b))
+	})
+}
+
+func TestAOPPFailures(t *testing.T) {
+	t.Run("no_accounts", func(t *testing.T) {
+		b := newAOPPTestBackend(t)
+		defer b.Close()
+
+		registerAOPPSigningKeystore(t, b)
+		for _, acct := range b.Accounts() {
+			require.NoError(t, b.SetAccountActive(acct.Config().Code, false))
+		}
+		params := defaultAOPPParams()
+		b.HandleURI("aopp:?" + params.Encode())
+		require.Equal(t, "user-approval", currentAOPPState(b))
+
+		postAOPPRoute(t, b, "/api/aopp/approve")
+
+		require.Equal(t, "error", currentAOPPState(b))
+		require.Equal(t, "aoppNoAccounts", currentAOPPErrorCode(b))
+	})
+}
diff --git a/backend/aopp_test.go b/backend/aopp_test.go
index 9f85738e6..93116adc0 100644
--- a/backend/aopp_test.go
+++ b/backend/aopp_test.go
@@ -307,7 +307,9 @@ func TestAOPPFailures(t *testing.T) {
 		params := defaultParams()
 		b.registerKeystore(&ks)
 		require.NoError(t, b.SetAccountActive("v0-55555555-btc-0", false))
+		b.DeregisterKeystore()
 		b.HandleURI("aopp:?" + params.Encode())
+		b.registerKeystore(&ks)
 		require.Equal(t, aoppStateError, b.AOPP().State)
 		require.Equal(t, errAOPPNoAccounts, b.AOPP().ErrorCode)
 	})
diff --git a/backend/handlers/aopp_approve_route_test.go b/backend/handlers/aopp_approve_route_test.go
new file mode 100644
index 000000000..1563eda47
--- /dev/null
+++ b/backend/handlers/aopp_approve_route_test.go
@@ -0,0 +1,70 @@
+package handlers_test
+
+import (
+	"os"
+	"path/filepath"
+	"strings"
+	"testing"
+
+	"github.com/stretchr/testify/require"
+)
+
+func TestAOPPFrontendApprovalSurface(t *testing.T) {
+	apiSource, err := os.ReadFile(filepath.Join("..", "..", "frontends", "web", "src", "api", "aopp.ts"))
+	require.NoError(t, err)
+	componentSource, err := os.ReadFile(filepath.Join("..", "..", "frontends", "web", "src", "components", "aopp", "aopp.tsx"))
+	require.NoError(t, err)
+
+	api := string(apiSource)
+	component := string(componentSource)
+	require.Contains(t, api, "'user-approval'")
+	require.Contains(t, api, "approve = (): Promise<null>")
+	require.Contains(t, api, "apiPost('aopp/approve')")
+
+	approvalIndex := strings.Index(component, "case 'user-approval':")
+	require.NotEqual(t, -1, approvalIndex)
+	approvalCase := component[approvalIndex:]
+	if nextCase := strings.Index(approvalCase[len("case 'user-approval':"):], "case '"); nextCase >= 0 {
+		approvalCase = approvalCase[:len("case 'user-approval':")+nextCase]
+	}
+	approvalSource := approvalCase
+	if !strings.Contains(approvalSource, "aoppAPI.approve") && !strings.Contains(approvalSource, "aoppAPI.cancel") {
+		if methodName := calledComponentMethod(approvalCase); methodName != "" {
+			approvalSource += componentMethodSource(component, methodName)
+		}
+	}
+	require.Contains(t, approvalSource, "callbackHost")
+	require.Contains(t, approvalSource, "aoppAPI.cancel")
+	require.Contains(t, approvalSource, "aoppAPI.approve")
+}
+
+func calledComponentMethod(source string) string {
+	const receiver = "this."
+	idx := strings.Index(source, receiver)
+	if idx < 0 {
+		return ""
+	}
+	rest := source[idx+len(receiver):]
+	end := 0
+	for end < len(rest) {
+		c := rest[end]
+		if (c >= 'a' && c <= 'z') || (c >= 'A' && c <= 'Z') || (c >= '0' && c <= '9') || c == '_' {
+			end++
+			continue
+		}
+		break
+	}
+	return rest[:end]
+}
+
+func componentMethodSource(component, methodName string) string {
+	idx := strings.Index(component, methodName)
+	if idx < 0 {
+		return ""
+	}
+	end := idx + 800
+	if end > len(component) {
+		end = len(component)
+	}
+	return component[idx:end]
+}
diff --git a/mimo_test_command.sh b/mimo_test_command.sh
new file mode 100755
--- /dev/null
+++ b/mimo_test_command.sh
@@ -0,0 +1,17 @@
+#!/bin/bash
+set -euo pipefail
+cd /testbed
+
+case "${1:-}" in
+  base)
+    go test -v -count=1 -run 'TestAOPPFailures/(wrong_version|missing_callback|invalid_callback|missing_msg|unsupported_asset)$' ./backend/
+    ;;
+  new)
+    go test -v -count=1 -run 'TestAOPPSuccess/(user-approval-before-account-selection|approve-continues-flow|approve-noops-outside-approval|approval-keystore-disconnect|cancel-from-approval-stops-before-account-selection)$|TestAOPPFailures/no_accounts$' ./backend/
+    go test -v -count=1 -run 'TestAOPP(ApproveRouteCallsBackend|FrontendApprovalSurface)$' ./backend/handlers/
+    ;;
+  *)
+    echo "usage: $0 base|new"
+    exit 2
+    ;;
+esac