diff --git a/lib/shared/typeahead-utils.js b/lib/shared/typeahead-utils.js
--- a/lib/shared/typeahead-utils.js
+++ b/lib/shared/typeahead-utils.js
@@ -15,6 +15,20 @@
   +end: number,
 };
 
+function getTypeaheadRegexMatches(
+  text: string,
+  selection: Selection,
+  regex: RegExp,
+): null | RegExp$matchResult {
+  if (
+    selection.start === selection.end &&
+    (selection.start === text.length || /\s/.test(text[selection.end]))
+  ) {
+    return text.slice(0, selection.start).match(regex);
+  }
+  return null;
+}
+
 function getTypeaheadUserSuggestions(
   userSearchIndex: SearchIndex,
   threadMembers: $ReadOnlyArray<RelativeMemberInfo>,
@@ -54,4 +68,8 @@
   return { newText, newSelectionStart };
 }
 
-export { getTypeaheadUserSuggestions, getNewTextAndSelection };
+export {
+  getTypeaheadUserSuggestions,
+  getNewTextAndSelection,
+  getTypeaheadRegexMatches,
+};
diff --git a/native/chat/chat-input-bar.react.js b/native/chat/chat-input-bar.react.js
--- a/native/chat/chat-input-bar.react.js
+++ b/native/chat/chat-input-bar.react.js
@@ -44,7 +44,11 @@
   draftKeyFromThreadID,
   colorIsDark,
 } from 'lib/shared/thread-utils';
-import type { Selection } from 'lib/shared/typeahead-utils';
+import {
+  getTypeaheadUserSuggestions,
+  getTypeaheadRegexMatches,
+  type Selection,
+} from 'lib/shared/typeahead-utils';
 import type { CalendarQuery } from 'lib/types/entry-types';
 import type { LoadingStatus } from 'lib/types/loading-types';
 import type { PhotoPaste } from 'lib/types/media-types';
@@ -89,8 +93,10 @@
 import type { LayoutEvent } from '../types/react-native';
 import { type AnimatedViewStyle, AnimatedView } from '../types/styles';
 import { runTiming } from '../utils/animation-utils';
+import { nativeTypeaheadRegex } from '../utils/typeahead-utils';
 import { ChatContext } from './chat-context';
 import type { ChatNavigationProp } from './chat.react';
+import TypeaheadTooltip from './typeahead-tooltip.react';
 
 /* eslint-disable import/no-named-as-default-member */
 const {
@@ -506,6 +512,56 @@
       );
     }
 
+    // we only try to match if there is end of text or whitespace after cursor
+    let typeaheadRegexMatches = null;
+
+    if (this.androidPreviousText) {
+      typeaheadRegexMatches = getTypeaheadRegexMatches(
+        this.androidPreviousText,
+        this.state.selection,
+        nativeTypeaheadRegex,
+      );
+    } else if (this.iosPreviousSelection) {
+      typeaheadRegexMatches = getTypeaheadRegexMatches(
+        this.state.text,
+        this.iosPreviousSelection,
+        nativeTypeaheadRegex,
+      );
+    } else {
+      typeaheadRegexMatches = getTypeaheadRegexMatches(
+        this.state.text,
+        this.state.selection,
+        nativeTypeaheadRegex,
+      );
+    }
+
+    let typeaheadTooltip = null;
+
+    if (typeaheadRegexMatches) {
+      const typeaheadMatchedStrings = {
+        textBeforeAtSymbol: typeaheadRegexMatches[1] ?? '',
+        usernamePrefix: typeaheadRegexMatches[4] ?? '',
+      };
+
+      const suggestedUsers = getTypeaheadUserSuggestions(
+        this.props.userSearchIndex,
+        this.props.threadMembers,
+        this.props.viewerID,
+        typeaheadMatchedStrings.usernamePrefix,
+      );
+
+      if (suggestedUsers.length > 0) {
+        typeaheadTooltip = (
+          <TypeaheadTooltip
+            text={this.state.text}
+            matchedStrings={typeaheadMatchedStrings}
+            suggestedUsers={suggestedUsers}
+            focusAndUpdateTextAndSelection={this.focusAndUpdateTextAndSelection}
+          />
+        );
+      }
+    }
+
     let content;
     const defaultMembersAreVoiced = checkIfDefaultMembersAreVoiced(
       this.props.threadInfo,
@@ -551,6 +607,7 @@
         style={this.props.styles.container}
         onLayout={this.props.onInputBarLayout}
       >
+        {typeaheadTooltip}
         {joinButton}
         {content}
         {keyboardInputHost}
diff --git a/native/chat/typeahead-tooltip.react.js b/native/chat/typeahead-tooltip.react.js
--- a/native/chat/typeahead-tooltip.react.js
+++ b/native/chat/typeahead-tooltip.react.js
@@ -6,13 +6,13 @@
 
 import {
   type TypeaheadMatchedStrings,
+  type Selection,
   getNewTextAndSelection,
 } from 'lib/shared/typeahead-utils';
 import type { RelativeMemberInfo } from 'lib/types/thread-types';
 
 import Button from '../components/button.react';
 import { useStyles } from '../themes/colors';
-import type { Selection } from './chat-input-bar.react';
 
 export type TypeaheadTooltipProps = {
   +text: string,