diff --git a/CHANGELOG.md b/CHANGELOG.md
index ec6d0cc..fad9aa6 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -11,8 +11,11 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 
 ### New features
 
+* Added `.app(*, echo=)` support. This allows for chatlas to change the echo behavior when running the Shiny app. (#31)
+
 ### Bug fixes
 
+* Fix broken `Chat`'s Shiny app when `.app(*, stream=True)` by using async chat tools. (#31)
 * Update formatting of exported markdown to use `repr()` instead of `str()` when exporting tool call results. (#30)
 
 ## [0.3.0] - 2024-12-20
diff --git a/chatlas/_chat.py b/chatlas/_chat.py
index 9989404..a75f43d 100644
--- a/chatlas/_chat.py
+++ b/chatlas/_chat.py
@@ -388,6 +388,7 @@ def app(
         port: int = 0,
         launch_browser: bool = True,
         bg_thread: Optional[bool] = None,
+        echo: Optional[Literal["text", "all", "none"]] = None,
         kwargs: Optional[SubmitInputArgsT] = None,
     ):
         """
@@ -404,6 +405,8 @@ def app(
         bg_thread
             Whether to run the app in a background thread. If `None`, the app will
             run in a background thread if the current environment is a notebook.
+        echo
+            Whether to echo text content, all content (i.e., tool calls), or no content. Defaults to `"none"` when `stream=True` and `"text"` when `stream=False`.
         kwargs
             Additional keyword arguments to pass to the method used for requesting
             the response.
@@ -438,10 +441,22 @@ async def _():
                     return
                 if stream:
                     await chat.append_message_stream(
-                        self.stream(user_input, kwargs=kwargs)
+                        await self.stream_async(
+                            user_input,
+                            kwargs=kwargs,
+                            echo=echo or "none",
+                        )
                     )
                 else:
-                    await chat.append_message(str(self.chat(user_input, kwargs=kwargs)))
+                    await chat.append_message(
+                        str(
+                            self.chat(
+                                user_input,
+                                kwargs=kwargs,
+                                echo=echo or "text",
+                            )
+                        )
+                    )
 
         app = App(app_ui, server)