diff --git a/gpio/hc_sr04/README.md b/gpio/hc_sr04/README.md
new file mode 100644
index 0000000..0d02656
--- /dev/null
+++ b/gpio/hc_sr04/README.md
@@ -0,0 +1,4 @@
+## Original version from: [SquachWare hc_sr04](https://github.com/skizzophrenic/SquachWare-CFW/tree/dev/applications/plugins/hc_sr04)
+
+
+## (5V -> VCC) / (GND -> GND) / (13|TX -> Trig) / (14|RX -> Echo)
\ No newline at end of file
diff --git a/gpio/hc_sr04/application.fam b/gpio/hc_sr04/application.fam
new file mode 100644
index 0000000..da91a08
--- /dev/null
+++ b/gpio/hc_sr04/application.fam
@@ -0,0 +1,14 @@
+App(
+    appid="HC_SR04_Dist_Sensor",
+    name="[HC-SR] Dist. Sensor",
+    apptype=FlipperAppType.EXTERNAL,
+    entry_point="hc_sr04_app",
+    cdefines=["APP_HC_SR04"],
+    requires=[
+        "gui",
+    ],
+    stack_size=2 * 1024,
+    order=20,
+    fap_icon="dist_sensor10px.png",
+    fap_category="GPIO",
+)
\ No newline at end of file
diff --git a/gpio/hc_sr04/dist_sensor10px.png b/gpio/hc_sr04/dist_sensor10px.png
new file mode 100644
index 0000000..af9aa73
Binary files /dev/null and b/gpio/hc_sr04/dist_sensor10px.png differ
diff --git a/gpio/hc_sr04/hc_sr04.c b/gpio/hc_sr04/hc_sr04.c
new file mode 100644
index 0000000..dbbf4f3
--- /dev/null
+++ b/gpio/hc_sr04/hc_sr04.c
@@ -0,0 +1,273 @@
+// insired by
+// https://github.com/esphome/esphome/blob/ac0d921413c3884752193fe568fa82853f0f99e9/esphome/components/ultrasonic/ultrasonic_sensor.cpp
+// Ported and modified by @xMasterX
+
+#include <furi.h>
+#include <furi_hal_power.h>
+#include <furi_hal_console.h>
+#include <gui/gui.h>
+#include <input/input.h>
+#include <stdlib.h>
+#include <gui/elements.h>
+#include <notification/notification.h>
+#include <notification/notification_messages.h>
+
+typedef enum {
+    EventTypeTick,
+    EventTypeKey,
+} EventType;
+
+typedef struct {
+    EventType type;
+    InputEvent input;
+} PluginEvent;
+
+typedef struct {
+    NotificationApp* notification;
+    bool have_5v;
+    bool measurement_made;
+    uint32_t echo; // ms
+    float distance; // meters
+} PluginState;
+
+const NotificationSequence sequence_done = {
+    &message_display_backlight_on,
+    &message_green_255,
+    &message_note_c5,
+    &message_delay_50,
+    &message_sound_off,
+    NULL,
+};
+
+static void render_callback(Canvas* const canvas, void* ctx) {
+    const PluginState* plugin_state = acquire_mutex((ValueMutex*)ctx, 25);
+    if(plugin_state == NULL) {
+        return;
+    }
+    // border around the edge of the screen
+    // canvas_draw_frame(canvas, 0, 0, 128, 64);
+
+    canvas_set_font(canvas, FontPrimary);
+    elements_multiline_text_aligned(
+        canvas, 64, 2, AlignCenter, AlignTop, "HC-SR04 Ultrasonic\nDistance Sensor");
+
+    canvas_set_font(canvas, FontSecondary);
+
+    if(!plugin_state->have_5v) {
+        elements_multiline_text_aligned(
+            canvas,
+            4,
+            28,
+            AlignLeft,
+            AlignTop,
+            "5V on GPIO must be\nenabled, or USB must\nbe connected.");
+    } else {
+        if(!plugin_state->measurement_made) {
+            elements_multiline_text_aligned(
+                canvas, 64, 28, AlignCenter, AlignTop, "Press OK button to measure");
+            elements_multiline_text_aligned(
+                canvas, 64, 40, AlignCenter, AlignTop, "13/TX -> Trig\n14/RX -> Echo");
+        } else {
+            elements_multiline_text_aligned(canvas, 4, 28, AlignLeft, AlignTop, "Readout:");
+
+            FuriString* str_buf;
+            str_buf = furi_string_alloc();
+            furi_string_printf(str_buf, "Echo: %ld ms", plugin_state->echo);
+
+            canvas_draw_str_aligned(
+                canvas, 8, 38, AlignLeft, AlignTop, furi_string_get_cstr(str_buf));
+            furi_string_printf(str_buf, "Distance: %02f m", (double)plugin_state->distance);
+            canvas_draw_str_aligned(
+                canvas, 8, 48, AlignLeft, AlignTop, furi_string_get_cstr(str_buf));
+
+            furi_string_free(str_buf);
+        }
+    }
+
+    release_mutex((ValueMutex*)ctx, plugin_state);
+}
+
+static void input_callback(InputEvent* input_event, FuriMessageQueue* event_queue) {
+    furi_assert(event_queue);
+
+    PluginEvent event = {.type = EventTypeKey, .input = *input_event};
+    furi_message_queue_put(event_queue, &event, FuriWaitForever);
+}
+
+static void hc_sr04_state_init(PluginState* const plugin_state) {
+    plugin_state->echo = -1;
+    plugin_state->distance = -1;
+    plugin_state->measurement_made = false;
+
+    furi_hal_power_suppress_charge_enter();
+
+    plugin_state->have_5v = false;
+    if(furi_hal_power_is_otg_enabled() || furi_hal_power_is_charging()) {
+        plugin_state->have_5v = true;
+    } else {
+        furi_hal_power_enable_otg();
+        plugin_state->have_5v = true;
+    }
+}
+
+float hc_sr04_ms_to_m(uint32_t ms) {
+    const float speed_sound_m_per_s = 343.0f;
+    const float time_s = ms / 1e3f;
+    const float total_dist = time_s * speed_sound_m_per_s;
+    return total_dist / 2.0f;
+}
+
+static void hc_sr04_measure(PluginState* const plugin_state) {
+    //plugin_state->echo = 1;
+    //return;
+
+    if(!plugin_state->have_5v) {
+        if(furi_hal_power_is_otg_enabled() || furi_hal_power_is_charging()) {
+            plugin_state->have_5v = true;
+        } else {
+            return;
+        }
+    }
+
+    //furi_hal_light_set(LightRed, 0xFF);
+    notification_message(plugin_state->notification, &sequence_blink_start_yellow);
+
+    const uint32_t timeout_ms = 2000;
+    // Pin 13 / TX -> Trig
+    furi_hal_gpio_write(&gpio_usart_tx, false);
+    furi_hal_gpio_init(&gpio_usart_tx, GpioModeOutputPushPull, GpioPullNo, GpioSpeedVeryHigh);
+
+    // Pin 14 / RX -> Echo
+    furi_hal_gpio_write(&gpio_usart_rx, false);
+    furi_hal_gpio_init(&gpio_usart_rx, GpioModeInput, GpioPullNo, GpioSpeedVeryHigh);
+
+    //FURI_CRITICAL_ENTER();
+    // 10 ms pulse on TX
+    furi_hal_gpio_write(&gpio_usart_tx, true);
+    furi_delay_ms(10);
+    furi_hal_gpio_write(&gpio_usart_tx, false);
+
+    // TODO change from furi_get_tick(), which returns ms,
+    // to DWT->CYCCNT, which is a more precise counter with
+    // us precision (see furi_hal_cortex_delay_us)
+
+    const uint32_t start = furi_get_tick();
+
+    while(furi_get_tick() - start < timeout_ms && furi_hal_gpio_read(&gpio_usart_rx))
+        ;
+    while(furi_get_tick() - start < timeout_ms && !furi_hal_gpio_read(&gpio_usart_rx))
+        ;
+
+    const uint32_t pulse_start = furi_get_tick();
+
+    while(furi_get_tick() - start < timeout_ms && furi_hal_gpio_read(&gpio_usart_rx))
+        ;
+
+    const uint32_t pulse_end = furi_get_tick();
+    //FURI_CRITICAL_EXIT();
+
+    plugin_state->echo = pulse_end - pulse_start;
+    plugin_state->distance = hc_sr04_ms_to_m(pulse_end - pulse_start);
+    plugin_state->measurement_made = true;
+
+    //furi_hal_light_set(LightRed, 0x00);
+    notification_message(plugin_state->notification, &sequence_blink_stop);
+    notification_message(plugin_state->notification, &sequence_done);
+}
+
+int32_t hc_sr04_app() {
+    FuriMessageQueue* event_queue = furi_message_queue_alloc(8, sizeof(PluginEvent));
+
+    PluginState* plugin_state = malloc(sizeof(PluginState));
+
+    hc_sr04_state_init(plugin_state);
+
+    furi_hal_console_disable();
+
+    ValueMutex state_mutex;
+    if(!init_mutex(&state_mutex, plugin_state, sizeof(PluginState))) {
+        FURI_LOG_E("hc_sr04", "cannot create mutex\r\n");
+        if(furi_hal_power_is_otg_enabled()) {
+            furi_hal_power_disable_otg();
+        }
+        furi_hal_console_enable();
+        furi_hal_power_suppress_charge_exit();
+        furi_message_queue_free(event_queue);
+        free(plugin_state);
+        return 255;
+    }
+
+    plugin_state->notification = furi_record_open(RECORD_NOTIFICATION);
+
+    // Set system callbacks
+    ViewPort* view_port = view_port_alloc();
+    view_port_draw_callback_set(view_port, render_callback, &state_mutex);
+    view_port_input_callback_set(view_port, input_callback, event_queue);
+
+    // Open GUI and register view_port
+    Gui* gui = furi_record_open(RECORD_GUI);
+    gui_add_view_port(gui, view_port, GuiLayerFullscreen);
+
+    PluginEvent event;
+    for(bool processing = true; processing;) {
+        FuriStatus event_status = furi_message_queue_get(event_queue, &event, 100);
+
+        PluginState* plugin_state = (PluginState*)acquire_mutex_block(&state_mutex);
+
+        if(event_status == FuriStatusOk) {
+            // press events
+            if(event.type == EventTypeKey) {
+                if(event.input.type == InputTypePress) {
+                    switch(event.input.key) {
+                    case InputKeyUp:
+                    case InputKeyDown:
+                    case InputKeyRight:
+                    case InputKeyLeft:
+                        break;
+                    case InputKeyOk:
+                        hc_sr04_measure(plugin_state);
+                        break;
+                    case InputKeyBack:
+                        processing = false;
+                        break;
+                    default:
+                        break;
+                    }
+                }
+            }
+        }
+
+        view_port_update(view_port);
+        release_mutex(&state_mutex, plugin_state);
+    }
+
+    if(furi_hal_power_is_otg_enabled()) {
+        furi_hal_power_disable_otg();
+    }
+    furi_hal_power_suppress_charge_exit();
+
+    // Return TX / RX back to usart mode
+    furi_hal_gpio_init_ex(
+        &gpio_usart_tx,
+        GpioModeAltFunctionPushPull,
+        GpioPullUp,
+        GpioSpeedVeryHigh,
+        GpioAltFn7USART1);
+    furi_hal_gpio_init_ex(
+        &gpio_usart_rx,
+        GpioModeAltFunctionPushPull,
+        GpioPullUp,
+        GpioSpeedVeryHigh,
+        GpioAltFn7USART1);
+    furi_hal_console_enable();
+
+    view_port_enabled_set(view_port, false);
+    gui_remove_view_port(gui, view_port);
+    furi_record_close(RECORD_GUI);
+    furi_record_close(RECORD_NOTIFICATION);
+    view_port_free(view_port);
+    furi_message_queue_free(event_queue);
+    delete_mutex(&state_mutex);
+
+    return 0;
+}
\ No newline at end of file