diff --git a/lib/shared/reaction-utils.js b/lib/shared/reaction-utils.js
new file mode 100644
--- /dev/null
+++ b/lib/shared/reaction-utils.js
@@ -0,0 +1,29 @@
+// @flow
+
+import invariant from 'invariant';
+
+import type { MessageReactionInfo } from '../selectors/chat-selectors';
+
+function stringForReactionList(
+  reactions: $ReadOnlyMap<string, MessageReactionInfo>,
+): string {
+  let reactionText = '';
+  let index = 0;
+  for (const key of reactions.keys()) {
+    const reactionInfo = reactions.get(key);
+    invariant(reactionInfo, 'reactionInfo should be set');
+
+    if (index > 0) {
+      reactionText += ' ';
+    }
+    reactionText += key;
+    if (reactionInfo.users.size > 1) {
+      reactionText += ` ${reactionInfo.users.size}`;
+    }
+    index++;
+  }
+
+  return reactionText;
+}
+
+export { stringForReactionList };