diff --git a/app/actions/usersTyping.js b/app/actions/usersTyping.js
deleted file mode 100644
index fb8f5980b..000000000
--- a/app/actions/usersTyping.js
+++ /dev/null
@@ -1,21 +0,0 @@
-import { USERS_TYPING } from './actionsTypes';
-
-export function addUserTyping(username) {
-	return {
-		type: USERS_TYPING.ADD,
-		username
-	};
-}
-
-export function removeUserTyping(username) {
-	return {
-		type: USERS_TYPING.REMOVE,
-		username
-	};
-}
-
-export function clearUserTyping() {
-	return {
-		type: USERS_TYPING.CLEAR
-	};
-}
diff --git a/app/actions/usersTyping.ts b/app/actions/usersTyping.ts
new file mode 100644
index 000000000..19077ce65
--- /dev/null
+++ b/app/actions/usersTyping.ts
@@ -0,0 +1,29 @@
+import { Action } from 'redux';
+
+import { USERS_TYPING } from './actionsTypes';
+
+export interface IUsersTypingGenericAction extends Action {
+	username: string;
+}
+
+export type TActionUserTyping = IUsersTypingGenericAction & Action;
+
+export function addUserTyping(username: string): IUsersTypingGenericAction {
+	return {
+		type: USERS_TYPING.ADD,
+		username
+	};
+}
+
+export function removeUserTyping(username: string): IUsersTypingGenericAction {
+	return {
+		type: USERS_TYPING.REMOVE,
+		username
+	};
+}
+
+export function clearUserTyping(): Action {
+	return {
+		type: USERS_TYPING.CLEAR
+	};
+}
diff --git a/app/containers/RoomHeader/index.tsx b/app/containers/RoomHeader/index.tsx
index fb00bc10c..4c21ecba2 100644
--- a/app/containers/RoomHeader/index.tsx
+++ b/app/containers/RoomHeader/index.tsx
@@ -1,10 +1,11 @@
+import { dequal } from 'dequal';
 import React, { Component } from 'react';
 import { connect } from 'react-redux';
-import { dequal } from 'dequal';
 
-import RoomHeader from './RoomHeader';
+import { IApplicationState } from '../../definitions';
 import { withDimensions } from '../../dimensions';
 import I18n from '../../i18n';
+import RoomHeader from './RoomHeader';
 
 interface IRoomHeaderContainerProps {
 	title: string;
@@ -122,8 +123,8 @@ class RoomHeaderContainer extends Component<IRoomHeaderContainerProps, any> {
 	}
 }
 
-const mapStateToProps = (state: any, ownProps: any) => {
-	let statusText;
+const mapStateToProps = (state: IApplicationState, ownProps: any) => {
+	let statusText = '';
 	let status = 'offline';
 	const { roomUserId, type, visitor = {}, tmid } = ownProps;
 
diff --git a/app/definitions/redux/index.ts b/app/definitions/redux/index.ts
index 12f673f90..7dc67310e 100644
--- a/app/definitions/redux/index.ts
+++ b/app/definitions/redux/index.ts
@@ -6,6 +6,7 @@ import { IActionRoles } from '../../actions/roles';
 import { TActionSelectedUsers } from '../../actions/selectedUsers';
 import { IActionSettings } from '../../actions/settings';
 import { TActionSortPreferences } from '../../actions/sortPreferences';
+import { TActionUserTyping } from '../../actions/usersTyping';
 // REDUCERS
 import { IActiveUsers } from '../../reducers/activeUsers';
 import { IEncryption } from '../../reducers/encryption';
@@ -45,4 +46,5 @@ export type TApplicationActions = TActionActiveUsers &
 	IActionRoles &
 	IActionSettings &
 	TActionEncryption &
-	TActionSortPreferences;
+	TActionSortPreferences &
+  TActionUserTyping;
diff --git a/app/reducers/activeUsers.ts b/app/reducers/activeUsers.ts
index 9877a5ceb..1c32a13fb 100644
--- a/app/reducers/activeUsers.ts
+++ b/app/reducers/activeUsers.ts
@@ -4,7 +4,7 @@ import { SET_ACTIVE_USERS } from '../actions/actionsTypes';
 type TUserStatus = 'online' | 'offline';
 export interface IActiveUser {
 	status: TUserStatus;
-	statusText?: string;
+	statusText: string;
 }
 
 export interface IActiveUsers {
diff --git a/app/reducers/usersTyping.test.ts b/app/reducers/usersTyping.test.ts
new file mode 100644
index 000000000..26e527882
--- /dev/null
+++ b/app/reducers/usersTyping.test.ts
@@ -0,0 +1,30 @@
+import { addUserTyping, removeUserTyping, clearUserTyping } from '../actions/usersTyping';
+import { mockedStore } from './mockedStore';
+import { initialState } from './usersTyping';
+
+describe('test usersTyping reducer', () => {
+	it('should return initial state', () => {
+		const state = mockedStore.getState().usersTyping;
+		expect(state).toEqual(initialState);
+	});
+
+	it('should return modified store after addUserTyping', () => {
+		mockedStore.dispatch(addUserTyping('diego'));
+		mockedStore.dispatch(addUserTyping('carlos'));
+		mockedStore.dispatch(addUserTyping('maria'));
+		const state = mockedStore.getState().usersTyping;
+		expect(state).toEqual(['diego', 'carlos', 'maria']);
+	});
+
+	it('should return modified store after removeUserTyping', () => {
+		mockedStore.dispatch(removeUserTyping('diego'));
+		const state = mockedStore.getState().usersTyping;
+		expect(state).toEqual(['carlos', 'maria']);
+	});
+
+	it('should return initial state after reset', () => {
+		mockedStore.dispatch(clearUserTyping());
+		const state = mockedStore.getState().usersTyping;
+		expect(state).toEqual(initialState);
+	});
+});
diff --git a/app/reducers/usersTyping.js b/app/reducers/usersTyping.ts
similarity index 72%
rename from app/reducers/usersTyping.js
rename to app/reducers/usersTyping.ts
index acecab632..ecfbbb77d 100644
--- a/app/reducers/usersTyping.js
+++ b/app/reducers/usersTyping.ts
@@ -1,8 +1,11 @@
 import { USERS_TYPING } from '../actions/actionsTypes';
+import { TApplicationActions } from '../definitions';
 
-const initialState = [];
+export type IUsersTyping = string[];
 
-export default function usersTyping(state = initialState, action) {
+export const initialState: IUsersTyping = [];
+
+export default function usersTyping(state = initialState, action: TApplicationActions): IUsersTyping {
 	switch (action.type) {
 		case USERS_TYPING.ADD:
 			if (state.findIndex(item => item === action.username) === -1) {