diff --git a/edxp-core/build.gradle b/edxp-core/build.gradle
index 712fe618..c13d76a6 100644
--- a/edxp-core/build.gradle
+++ b/edxp-core/build.gradle
@@ -38,6 +38,7 @@ dependencies {
     implementation 'rikka.ndk:riru:10'
     implementation project(path: ':sandhook-hooklib')
     compileOnly project(':hiddenapi-stubs')
+    compileOnly project(':key-selector')
     compileOnly 'androidx.annotation:annotation:1.1.0'
 }
 
@@ -152,6 +153,7 @@ afterEvaluate {
         def prepareMagiskFilesTask = task("prepareMagiskFiles${variantCapped}", type: Delete) {
             dependsOn "assemble${variantCapped}"
             dependsOn tasks.getByPath(":sandhook-hooklib:copySandHook${variantCapped}LibraryToMagiskTemplate")
+            dependsOn tasks.getByPath(":key-selector:copyKeySelector${variantCapped}LibraryToMagiskTemplate")
             doFirst {
                 copy {
                     from "${projectDir}/tpl/module.prop.tpl"
diff --git a/key-selector/.gitignore b/key-selector/.gitignore
new file mode 100644
index 00000000..42afabfd
--- /dev/null
+++ b/key-selector/.gitignore
@@ -0,0 +1 @@
+/build
\ No newline at end of file
diff --git a/key-selector/build.gradle b/key-selector/build.gradle
new file mode 100644
index 00000000..b3b8d2d7
--- /dev/null
+++ b/key-selector/build.gradle
@@ -0,0 +1,76 @@
+apply plugin: 'com.android.library'
+
+android {
+    compileSdkVersion androidCompileSdkVersion.toInteger()
+
+    defaultConfig {
+        minSdkVersion androidMinSdkVersion.toInteger()
+        targetSdkVersion androidTargetSdkVersion.toInteger()
+
+        externalNativeBuild {
+            cmake {
+                abiFilters 'arm64-v8a', 'armeabi-v7a', 'x86', 'x86_64'
+                cppFlags "-std=c++17"
+                cFlags "-std=gnu99"
+            }
+        }
+    }
+
+    buildTypes {
+        debug {
+            externalNativeBuild {
+                cmake {
+                    cppFlags "-O0"
+                    cFlags "-O0"
+                }
+            }
+        }
+        release {
+            externalNativeBuild {
+                cmake {
+                    cppFlags "-fvisibility=hidden -fvisibility-inlines-hidden -O2 -s -Wno-unused-value"
+                    cFlags "-fvisibility=hidden -fvisibility-inlines-hidden -O2 -s -Wno-unused-value"
+                }
+            }
+        }
+    }
+    externalNativeBuild {
+        cmake {
+            path "src/main/cpp/CMakeLists.txt"
+        }
+    }
+}
+
+afterEvaluate {
+    android.libraryVariants.all { variant ->
+        def variantNameCapped = variant.name.capitalize()
+        def variantNameLowered = variant.name.toLowerCase()
+
+        task("copyKeySelector${variantNameCapped}LibraryToMagiskTemplate") {
+            def libPathRelease = "${buildDir}/intermediates/cmake/${variantNameLowered}/obj"
+            doLast {
+                copy {
+                    include "key_selector"
+                    from "${libPathRelease}/armeabi-v7a"
+                    into "${zipPathMagiskReleasePath}/system/bin"
+                }
+                copy {
+                    include "key_selector"
+                    from "${libPathRelease}/arm64-v8a"
+                    into "${zipPathMagiskReleasePath}/system/bin64"
+                }
+                copy {
+                    include "key_selector"
+                    from "${libPathRelease}/x86"
+                    into "${zipPathMagiskReleasePath}/system_x86/bin"
+                }
+                copy {
+                    include "key_selector"
+                    from "${libPathRelease}/x86_64"
+                    into "${zipPathMagiskReleasePath}/system_x86/bin64"
+                }
+            }
+        }
+
+    }
+}
\ No newline at end of file
diff --git a/key-selector/src/main/AndroidManifest.xml b/key-selector/src/main/AndroidManifest.xml
new file mode 100644
index 00000000..cbe21451
--- /dev/null
+++ b/key-selector/src/main/AndroidManifest.xml
@@ -0,0 +1,5 @@
+<?xml version="1.0" encoding="utf-8"?>
+<manifest xmlns:android="http://schemas.android.com/apk/res/android"
+    package="com.elderdrivers.riru.edxp.key_selector">
+
+</manifest>
\ No newline at end of file
diff --git a/key-selector/src/main/cpp/CMakeLists.txt b/key-selector/src/main/cpp/CMakeLists.txt
new file mode 100644
index 00000000..10e183ff
--- /dev/null
+++ b/key-selector/src/main/cpp/CMakeLists.txt
@@ -0,0 +1,5 @@
+cmake_minimum_required(VERSION 3.4.1)
+
+project(key_selector)
+
+add_executable(key_selector key_selector.cpp)
diff --git a/key-selector/src/main/cpp/key_selector.cpp b/key-selector/src/main/cpp/key_selector.cpp
new file mode 100644
index 00000000..7e31fe1c
--- /dev/null
+++ b/key-selector/src/main/cpp/key_selector.cpp
@@ -0,0 +1,298 @@
+/*
+ * Copyright (C) 2010 The Android Open Source Project
+ * Copyright (C) 2015-2016 The CyanogenMod Project
+ * Copyright (C) 2021 LSPosed
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#include <iostream>
+#include <cstdlib>
+#include <dirent.h>
+#include <fcntl.h>
+#include <cstring>
+#include <sys/ioctl.h>
+#include <sys/inotify.h>
+#include <sys/poll.h>
+#include <linux/input.h>
+#include <cerrno>
+#include <unistd.h>
+#include <stdexcept>
+
+#include "key_selector.h"
+
+// Global variables
+static struct pollfd *ufds;
+static char **device_names;
+static int nfds;
+
+static int open_device(const char *device)
+{
+    int version;
+    int fd;
+    int clkid = CLOCK_MONOTONIC;
+    struct pollfd *new_ufds;
+    char **new_device_names;
+    char name[80];
+    char location[80];
+    char idstr[80];
+    struct input_id id;
+
+    fd = open(device, O_RDWR);
+    if (fd < 0) {
+        return -1;
+    }
+
+    if (ioctl(fd, EVIOCGVERSION, &version)) {
+        return -1;
+    }
+
+    if (ioctl(fd, EVIOCGID, &id)) {
+        return -1;
+    }
+
+    name[sizeof(name) - 1] = '\0';
+    location[sizeof(location) - 1] = '\0';
+    idstr[sizeof(idstr) - 1] = '\0';
+
+    if (ioctl(fd, EVIOCGNAME(sizeof(name) - 1), &name) < 1) {
+        name[0] = '\0';
+    }
+
+    if (ioctl(fd, EVIOCGPHYS(sizeof(location) - 1), &location) < 1) {
+        location[0] = '\0';
+    }
+
+    if (ioctl(fd, EVIOCGUNIQ(sizeof(idstr) - 1), &idstr) < 1) {
+        idstr[0] = '\0';
+    }
+
+    if (ioctl(fd, EVIOCSCLOCKID, &clkid) != 0) {
+        // a non-fatal error
+    }
+
+    new_ufds = static_cast<pollfd *>(realloc(ufds, sizeof(ufds[0]) * (nfds + 1)));
+    if (new_ufds == nullptr) {
+        return -1;
+    }
+
+    ufds = new_ufds;
+    new_device_names = static_cast<char **>(realloc(device_names,
+                                                    sizeof(device_names[0]) * (nfds + 1)));
+    if (new_device_names == nullptr) {
+        return -1;
+    }
+
+    device_names = new_device_names;
+
+    ufds[nfds].fd = fd;
+    ufds[nfds].events = POLLIN;
+    device_names[nfds] = strdup(device);
+    nfds++;
+
+    return 0;
+}
+
+int close_device(const char *device)
+{
+    int i;
+    for (i = 1; i < nfds; i++) {
+        if (strcmp(device_names[i], device) == 0) {
+            int count = nfds - i - 1;
+            free(device_names[i]);
+            memmove(device_names + i, device_names + i + 1,
+                    sizeof(device_names[0]) * count);
+            memmove(ufds + i, ufds + i + 1, sizeof(ufds[0]) * count);
+            nfds--;
+            return 0;
+        }
+    }
+    return -1;
+}
+
+static int read_notify(const char *dirname, int nfd)
+{
+    int res;
+    char devname[PATH_MAX];
+    char *filename;
+    char event_buf[512];
+    int event_size;
+    int event_pos = 0;
+    struct inotify_event *event;
+
+    res = read(nfd, event_buf, sizeof(event_buf));
+    if (res < (int)sizeof(*event)) {
+        if (errno == EINTR) {
+            return 0;
+        }
+        return 1;
+    }
+
+    strcpy(devname, dirname);
+    filename = devname + strlen(devname);
+    *filename++ = '/';
+
+    while (res >= (int)sizeof(*event)) {
+        event = (struct inotify_event *)(event_buf + event_pos);
+        if (event->len) {
+            strcpy(filename, event->name);
+            if (event->mask & IN_CREATE) {
+                open_device(devname);
+            } else {
+                close_device(devname);
+            }
+        }
+        event_size = sizeof(*event) + event->len;
+        res -= event_size;
+        event_pos += event_size;
+    }
+    return 0;
+}
+
+static int scan_dir(const char *dirname)
+{
+    char devname[PATH_MAX];
+    char *filename;
+    DIR *dir;
+    struct dirent *de;
+
+    dir = opendir(dirname);
+    if (dir == NULL) {
+        return -1;
+    }
+
+    strcpy(devname, dirname);
+    filename = devname + strlen(devname);
+    *filename++ = '/';
+
+    while ((de = readdir(dir))) {
+        if (de->d_name[0] == '.' && (de->d_name[1] == '\0' ||
+                                     (de->d_name[1] == '.' && de->d_name[2] == '\0'))) {
+            continue;
+        }
+
+        strcpy(filename, de->d_name);
+        open_device(devname);
+    }
+    closedir(dir);
+    return 0;
+}
+
+
+uint32_t get_event() {
+    int i;
+    int res;
+    struct input_event event;
+    const char *device_path = "/dev/input";
+    unsigned char keys;
+
+    keys = KEYCHECK_CHECK_VOLUMEDOWN | KEYCHECK_CHECK_VOLUMEUP;
+    nfds = 1;
+    ufds = static_cast<pollfd *>(calloc(1, sizeof(ufds[0])));
+    ufds[0].fd = inotify_init();
+    ufds[0].events = POLLIN;
+
+    res = inotify_add_watch(ufds[0].fd, device_path, IN_DELETE | IN_CREATE);
+    if (res < 0) {
+        throw std::logic_error("inotify_add_watch failed");
+    }
+
+    res = scan_dir(device_path);
+    if (res < 0) {
+        throw std::logic_error("scan dev failed");
+    }
+
+    while (true) {
+        poll(ufds, nfds, -1);
+        if (ufds[0].revents & POLLIN) {
+            read_notify(device_path, ufds[0].fd);
+        }
+
+        for (i = 1; i < nfds; i++) {
+            if ((ufds[i].revents) && (ufds[i].revents & POLLIN)) {
+                res = read(ufds[i].fd, &event, sizeof(event));
+                if (res < (int)sizeof(event)) {
+                    return 1;
+                }
+
+                // keypress only
+                if (event.value == 1) {
+                    if (event.code == KEY_VOLUMEDOWN &&
+                        (keys & KEYCHECK_CHECK_VOLUMEDOWN) != 0) {
+                        return KEYCHECK_PRESSED_VOLUMEDOWN;
+                    }
+                    else if (event.code == KEY_VOLUMEUP &&
+                             (keys & KEYCHECK_CHECK_VOLUMEUP) != 0) {
+                        return KEYCHECK_PRESSED_VOLUMEUP;
+                    }
+                }
+            }
+        }
+    }
+}
+
+int main() {
+    if (getuid() != 0) {
+        std::cout << "Root required" << std::endl;
+        exit(1);
+    }
+
+    // for phone which has no button
+    const uint16_t timeout = 20;
+    alarm(timeout);
+    auto sig_handler = [](int){
+        std::cout << "No operation after " << timeout << " seconds" << std::endl;
+        exit(YAHFA);
+    };
+    signal(SIGALRM, sig_handler);
+
+    int cursor = YAHFA;
+    const int cursor_max = SandHook;
+
+    auto print_status = [&cursor](){
+        std::cout << "\33[2K\r"; // clear this line
+        std::cout << "[";
+        std::cout << (cursor == YAHFA ? "x" : " ");
+        std::cout << "] YAHFA  [";
+        std::cout << (cursor == SandHook ? "x" : " ");
+        std::cout << "] SandHook" << std::flush;
+    };
+
+    std::cout << "Select variant. Use Volume Down to move and Volume Up to confirm." << std::endl;
+    std::cout << "The program will select YAHFA for you in " << timeout << " seconds if you don't have a physical volume button. " << std::endl;
+    print_status();
+    while (int event = get_event()) {
+        bool leave = false;
+        //std::cout << event << " " << cursor << std::endl;
+        switch (event) {
+            case KEYCHECK_PRESSED_VOLUMEUP:
+                leave = true;
+                break;
+            case KEYCHECK_PRESSED_VOLUMEDOWN:
+                cursor++;
+                if (cursor > cursor_max) {
+                    cursor = YAHFA;
+                }
+                break;
+            default:
+                std::cout << "ERROR\n";
+        }
+        print_status();
+        if (leave) {
+            break;
+        }
+    }
+
+    // std::cout << std::endl << cursor << std::endl;
+    return cursor;
+}
\ No newline at end of file
diff --git a/key-selector/src/main/cpp/key_selector.h b/key-selector/src/main/cpp/key_selector.h
new file mode 100644
index 00000000..730c4f0f
--- /dev/null
+++ b/key-selector/src/main/cpp/key_selector.h
@@ -0,0 +1,32 @@
+/*
+ * Copyright (C) 2015-2016 The CyanogenMod Project
+ * Copyright (C) 2021 LSPosed
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef __KEYCHECK_H__
+#define __KEYCHECK_H__
+
+// Constants: pressed keys
+#define KEYCHECK_CHECK_VOLUMEDOWN 0x01u
+#define KEYCHECK_CHECK_VOLUMEUP 0x02u
+#define KEYCHECK_PRESSED_VOLUMEDOWN 41u
+#define KEYCHECK_PRESSED_VOLUMEUP 42u
+
+enum Variant {
+    YAHFA = 0x11,
+    SandHook = 0x12,
+};
+
+#endif // __KEYCHECK_H__
\ No newline at end of file
diff --git a/settings.gradle b/settings.gradle
index 82bdba0d..e8f128de 100644
--- a/settings.gradle
+++ b/settings.gradle
@@ -1 +1 @@
-include ':edxp-core', ':hiddenapi-stubs', ':sandhook-hooklib', ':sandhook-annotation', ':app'
+include ':edxp-core', ':hiddenapi-stubs', ':sandhook-hooklib', ':sandhook-annotation', ':app', ':key-selector'