diff --git a/src/garmi_gui/__init__.py b/src/garmi_gui/__init__.py
index 9dda466..c3ad187 100644
--- a/src/garmi_gui/__init__.py
+++ b/src/garmi_gui/__init__.py
@@ -1,7 +1,8 @@
 """
 Copyright (c) 2024 Jean Elsner. All rights reserved.
 
-garmi-gui: The GARMI gui.
+garmi-gui: GUI for the GARMI robot's face screen with remote control
+to show images, play videos and sounds, and render text.
 """
 
 from __future__ import annotations
diff --git a/src/garmi_gui/control.py b/src/garmi_gui/control.py
index f07085a..836599c 100644
--- a/src/garmi_gui/control.py
+++ b/src/garmi_gui/control.py
@@ -6,6 +6,12 @@
 
 
 def main() -> None:
+    """Simple terminal program that allows you to connect to a GARMI GUI remotely
+    and execute commands. If you installed the package this function is installed
+    as an executable that can be called as
+    ``garmi-gui --hostname <gui-hostname> --port <gui-port>`` to connect with a
+    remote GUI running on the given hostname and port respectively.
+    """
     parser = argparse.ArgumentParser(description="Remote GUI Controller")
     parser.add_argument(
         "--hostname", type=str, default="localhost", help="Hostname of the remote GUI"
@@ -40,7 +46,14 @@ def main() -> None:
             proxy.show_video(video_path)
             print(f"Video '{video_path}' displayed.")
         elif choice == "4":
-            text = input("Enter the text to display: ")
+            print("Enter the text to display: ")
+            lines = []
+            while True:
+                line = input()
+                if line == "":
+                    break
+                lines.append(line)
+            text = "\n".join(lines)
             color_str = input("Enter the color (default is 0,255,255 cyan): ")
             font_size_str = input("Enter the font size (default is 100): ")
             color = (
diff --git a/src/garmi_gui/gui.py b/src/garmi_gui/gui.py
index c23c67c..2ea405d 100644
--- a/src/garmi_gui/gui.py
+++ b/src/garmi_gui/gui.py
@@ -2,6 +2,7 @@
 
 import argparse
 import pathlib
+import textwrap
 import threading
 from xmlrpc import server
 
@@ -12,7 +13,9 @@
 
 
 class GUI:
-    """GUI for the GARMI robot face display."""
+    """GUI for the GARMI robot face display.
+
+    The functions of this class are usually called remotely using xmlrpc."""
 
     def __init__(self, port: int, fullscreen: bool = True, testing: bool = False):
         self.fullscreen = fullscreen
@@ -23,6 +26,7 @@ def __init__(self, port: int, fullscreen: bool = True, testing: bool = False):
         self.sound: None | pygame.mixer.Sound = None
         self.stop_video_event = threading.Event()
         self.running = True
+        self.mux = threading.Lock()
 
         self.gui_thread = threading.Thread(target=self._run)
         self.gui_thread.start()
@@ -35,6 +39,8 @@ def __init__(self, port: int, fullscreen: bool = True, testing: bool = False):
         self.server_thread.start()
 
     def play_sound(self, sound_path: str) -> None:
+        """Plays a local sound file. If only a filename is given,
+        the file is searched for in the local resources directory."""
         self.stop_sound()
         self.sound = pygame.mixer.Sound(self.process_path(sound_path))
         self.sound.play()
@@ -46,21 +52,49 @@ def process_path(self, path: str) -> str:
         return str(RESOURCE_PATH / proc_path)
 
     def stop_sound(self) -> None:
+        """Stops playing sound if the GUI is currently playing a sound."""
         if self.sound is not None:
             self.sound.stop()
 
+    def wrap_text(self, text: str, font_size: int) -> str:
+        """Wraps a textstring so it will fit into the screen when displayed.
+        :py:func:`render_text` and :py:func:`show_text` will apply this to
+        any text arguments before rendering."""
+        proc: list[str] = []
+        for line in text.splitlines():
+            wrapped = textwrap.wrap(
+                line,
+                int(100 / font_size * 35 * self.screen.get_rect().width / 1280),
+                drop_whitespace=False,
+                replace_whitespace=False,
+            )
+            if wrapped:
+                proc.extend(wrapped)
+            else:
+                proc.append("")
+        return str.join("\n", proc)
+
     def show_text(
         self,
         text: str,
         color: tuple[int, int, int] = (0, 255, 255),
         font_size: int = 100,
     ) -> None:
+        """Displays a text on the GUI in the given color and font size.
+        The displayed text may contain newline but is also wrapped to fit the display."""
+        text = self.wrap_text(text, font_size)
         self.stop_video()
         self.screen.fill((0, 0, 0))
         font = pygame.font.Font(None, font_size)
-        text_surface = font.render(text, True, color)
-        text_rect = text_surface.get_rect(center=self.screen.get_rect().center)
-        self.screen.blit(text_surface, text_rect)
+        lines = text.splitlines()
+        bias_y = (len(lines) - 1) / 2 * font_size
+        with self.mux:
+            for line_number, line in enumerate(lines):
+                text_surface = font.render(line, True, color)
+                pos = list(self.screen.get_rect().center)
+                pos[1] += int(font_size * line_number - bias_y)
+                text_rect = text_surface.get_rect(center=pos)
+                self.screen.blit(text_surface, text_rect)
 
     def render_text(
         self,
@@ -69,7 +103,11 @@ def render_text(
         color: tuple[int, int, int] = (0, 255, 255),
         font_size: int = 100,
     ) -> None:
+        """Renders text on the GUI character by character with the speed
+        given in characters per second. Wraps text as necessary. Otherwise
+        functions like :py:func:`show_text`."""
         self.stop_video()
+        text = self.wrap_text(text, font_size)
 
         def render() -> None:
             font = pygame.font.Font(None, font_size)
@@ -81,27 +119,34 @@ def render() -> None:
                 for char in line:
                     if not self.running:
                         break
-                    self.screen.fill((0, 0, 0))
-                    for surface, rect in rendered_lines:
-                        self.screen.blit(surface, rect)
                     current_text += char
                     text_surface = font.render(current_text, True, color)
                     pos = list(self.screen.get_rect().center)
                     pos[1] += int(font_size * line_number - bias_y)
                     text_rect = text_surface.get_rect(center=pos)
-                    self.screen.blit(text_surface, text_rect)
+                    with self.mux:
+                        self.screen.fill((0, 0, 0))
+                        for surface, rect in rendered_lines:
+                            self.screen.blit(surface, rect)
+                        self.screen.blit(text_surface, text_rect)
                     self.clock.tick(speed)
                 rendered_lines.append((text_surface, text_rect))
 
         threading.Thread(target=render).start()
 
     def show_image(self, image_path: str) -> None:
+        """Displays a local image on the GUI. Relative paths are evaluated
+        relative to the resources directory."""
         self.stop_video()
         image = pygame.image.load(self.process_path(image_path)).convert()
         image = pygame.transform.smoothscale(image, self.screen.get_size())
-        self.screen.blit(image, (0, 0))
+        with self.mux:
+            self.screen.blit(image, (0, 0))
 
     def show_video(self, video_path: str) -> None:
+        """Plays a local video and displays it on the GUI.
+        The video will loop until something else is displayed
+        or :py:func:`stop_video` is called."""
         video_path = self.process_path(video_path)
         self.stop_video()
         if not pathlib.Path(video_path).exists():
@@ -126,9 +171,10 @@ def _play_video(self, video_path: str) -> None:
 
             frame = cv2.cvtColor(frame, cv2.COLOR_BGR2RGB)
             frame = pygame.image.frombuffer(frame.tobytes(), frame.shape[1::-1], "RGB")
-            self.screen.blit(
-                pygame.transform.smoothscale(frame, self.screen.get_size()), (0, 0)
-            )
+            with self.mux:
+                self.screen.blit(
+                    pygame.transform.smoothscale(frame, self.screen.get_size()), (0, 0)
+                )
 
             self.clock.tick(fps)
 
@@ -136,6 +182,7 @@ def _play_video(self, video_path: str) -> None:
         self.video_running = False
 
     def stop_video(self) -> None:
+        """Stops video if a video is currently shown on the GUI."""
         if self.video_running and self.video_thread is not None:
             self.stop_video_event.set()
             self.video_thread.join()
@@ -165,15 +212,17 @@ def _run(self) -> None:
                         and event.key == pygame.K_ESCAPE
                     ):
                         self.running = False
-                pygame.display.flip()
+                with self.mux:
+                    pygame.display.flip()
             except pygame.error:
                 self.running = False
 
-            self.clock.tick(10)  # Throttle loop to reduce CPU usage
+            self.clock.tick(30)  # Throttle loop to reduce CPU usage
 
         self.stop()
 
     def stop(self) -> None:
+        """Closes the GUI and stops any connected threads."""
         self.stop_video()
         self.server.shutdown()
         self.server_thread.join()
@@ -181,6 +230,9 @@ def stop(self) -> None:
 
 
 def start_gui() -> None:
+    """This function is installed as an executable and can be run as
+    ``garmi-gui --port <port>`` where an xmlrpc server is started, listening
+    on the given port."""
     parser = argparse.ArgumentParser()
     parser.add_argument(
         "--port", "-p", type=int, default=8000, help="Port of the xmlrpc server."
diff --git a/tests/test_gui.py b/tests/test_gui.py
index 4830e7a..4eef540 100644
--- a/tests/test_gui.py
+++ b/tests/test_gui.py
@@ -13,7 +13,7 @@
 
 
 def test_gui():
-    gui_instance = gui.GUI(8000, testing=True)
+    gui_instance = gui.GUI(8000, fullscreen=False, testing=True)
 
     gui_instance.show_image("eyes.png")
     time.sleep(0.1)
@@ -37,4 +37,16 @@ def test_gui():
     with pytest.raises(FileNotFoundError):
         gui_instance.show_video("unknown-video-path")
 
+    assert (
+        len(
+            gui_instance.wrap_text(
+                "This text should be wrapped.", font_size=200
+            ).splitlines()
+        )
+        > 1
+    )
+
+    assert gui_instance.screen.get_rect().width == 1280
+    assert gui_instance.screen.get_rect().height == 960
+
     gui_instance.stop()