diff --git a/src/ClientContext.tsx b/src/ClientContext.tsx
index 503c3f8f..5e0c3c1c 100644
--- a/src/ClientContext.tsx
+++ b/src/ClientContext.tsx
@@ -62,6 +62,7 @@ interface ClientState {
   changePassword: (password: string) => Promise<void>;
   logout: () => void;
   setClient: (client: MatrixClient, session: Session) => void;
+  error?: Error;
 }
 
 const ClientContext = createContext<ClientState>(null);
diff --git a/src/button/CopyButton.tsx b/src/button/CopyButton.tsx
index 480cd444..87c58da3 100644
--- a/src/button/CopyButton.tsx
+++ b/src/button/CopyButton.tsx
@@ -23,10 +23,10 @@ import { Button, ButtonVariant } from "./Button";
 
 interface Props {
   value: string;
-  children: JSX.Element;
+  children?: JSX.Element;
   className: string;
   variant: ButtonVariant;
-  copiedMessage: string;
+  copiedMessage?: string;
 }
 export function CopyButton({
   value,
diff --git a/src/form/Form.jsx b/src/form/Form.tsx
similarity index 58%
rename from src/form/Form.jsx
rename to src/form/Form.tsx
index 011fbb26..55dadaed 100644
--- a/src/form/Form.jsx
+++ b/src/form/Form.tsx
@@ -15,13 +15,26 @@ limitations under the License.
 */
 
 import classNames from "classnames";
-import React, { forwardRef } from "react";
+import React, { FormEventHandler, forwardRef } from "react";
+
 import styles from "./Form.module.css";
 
-export const Form = forwardRef(({ children, className, ...rest }, ref) => {
-  return (
-    <form {...rest} className={classNames(styles.form, className)} ref={ref}>
-      {children}
-    </form>
-  );
-});
+interface FormProps {
+  className: string;
+  onSubmit: FormEventHandler<HTMLFormElement>;
+  children: JSX.Element[];
+}
+
+export const Form = forwardRef<HTMLFormElement, FormProps>(
+  ({ children, className, onSubmit }, ref) => {
+    return (
+      <form
+        onSubmit={onSubmit}
+        className={classNames(styles.form, className)}
+        ref={ref}
+      >
+        {children}
+      </form>
+    );
+  }
+);
diff --git a/src/home/CallList.jsx b/src/home/CallList.tsx
similarity index 81%
rename from src/home/CallList.jsx
rename to src/home/CallList.tsx
index e4badf26..8b257234 100644
--- a/src/home/CallList.jsx
+++ b/src/home/CallList.tsx
@@ -16,14 +16,22 @@ limitations under the License.
 
 import React from "react";
 import { Link } from "react-router-dom";
+import { MatrixClient, RoomMember } from "matrix-js-sdk";
+
 import { CopyButton } from "../button";
 import { Facepile } from "../Facepile";
-import { Avatar } from "../Avatar";
+import { Avatar, Size } from "../Avatar";
 import styles from "./CallList.module.css";
 import { getRoomUrl } from "../matrix-utils";
 import { Body, Caption } from "../typography/Typography";
+import { GroupCallRoom } from "./useGroupCallRooms";
 
-export function CallList({ rooms, client, disableFacepile }) {
+interface CallListProps {
+  rooms: GroupCallRoom[];
+  client: MatrixClient;
+  disableFacepile?: boolean;
+}
+export function CallList({ rooms, client, disableFacepile }: CallListProps) {
   return (
     <>
       <div className={styles.callList}>
@@ -48,7 +56,14 @@ export function CallList({ rooms, client, disableFacepile }) {
     </>
   );
 }
-
+interface CallTileProps {
+  name: string;
+  avatarUrl: string;
+  roomId: string;
+  participants: RoomMember[];
+  client: MatrixClient;
+  disableFacepile?: boolean;
+}
 function CallTile({
   name,
   avatarUrl,
@@ -56,12 +71,12 @@ function CallTile({
   participants,
   client,
   disableFacepile,
-}) {
+}: CallTileProps) {
   return (
     <div className={styles.callTile}>
       <Link to={`/room/${roomId}`} className={styles.callTileLink}>
         <Avatar
-          size="lg"
+          size={Size.LG}
           bgKey={name}
           src={avatarUrl}
           fallback={name.slice(0, 1).toUpperCase()}
diff --git a/src/home/HomePage.jsx b/src/home/HomePage.tsx
similarity index 99%
rename from src/home/HomePage.jsx
rename to src/home/HomePage.tsx
index 89c9ecec..00f770fd 100644
--- a/src/home/HomePage.jsx
+++ b/src/home/HomePage.tsx
@@ -15,6 +15,7 @@ limitations under the License.
 */
 
 import React from "react";
+
 import { useClient } from "../ClientContext";
 import { ErrorView, LoadingView } from "../FullScreenView";
 import { UnauthenticatedView } from "./UnauthenticatedView";
diff --git a/src/home/JoinExistingCallModal.jsx b/src/home/JoinExistingCallModal.tsx
similarity index 76%
rename from src/home/JoinExistingCallModal.jsx
rename to src/home/JoinExistingCallModal.tsx
index 515baca1..b26c45d9 100644
--- a/src/home/JoinExistingCallModal.jsx
+++ b/src/home/JoinExistingCallModal.tsx
@@ -15,18 +15,26 @@ limitations under the License.
 */
 
 import React from "react";
+import { PressEvent } from "@react-types/shared";
+
 import { Modal, ModalContent } from "../Modal";
 import { Button } from "../button";
 import { FieldRow } from "../input/Input";
 import styles from "./JoinExistingCallModal.module.css";
 
-export function JoinExistingCallModal({ onJoin, ...rest }) {
+interface Props {
+  onJoin: (e: PressEvent) => void;
+  onClose: (e: PressEvent) => void;
+  // TODO: add used parameters for <Modal>
+  [index: string]: unknown;
+}
+export function JoinExistingCallModal({ onJoin, onClose, ...rest }: Props) {
   return (
     <Modal title="Join existing call?" isDismissable {...rest}>
       <ModalContent>
         <p>This call already exists, would you like to join?</p>
         <FieldRow rightAlign className={styles.buttons}>
-          <Button onPress={rest.onClose}>No</Button>
+          <Button onPress={onClose}>No</Button>
           <Button onPress={onJoin}>Yes, join call</Button>
         </FieldRow>
       </ModalContent>
diff --git a/src/home/RegisteredView.jsx b/src/home/RegisteredView.tsx
similarity index 84%
rename from src/home/RegisteredView.jsx
rename to src/home/RegisteredView.tsx
index b5fef745..4d190dde 100644
--- a/src/home/RegisteredView.jsx
+++ b/src/home/RegisteredView.tsx
@@ -14,7 +14,15 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
-import React, { useState, useCallback } from "react";
+import React, {
+  useState,
+  useCallback,
+  FormEvent,
+  FormEventHandler,
+} from "react";
+import { useHistory } from "react-router-dom";
+import { MatrixClient } from "matrix-js-sdk";
+
 import { createRoom, roomAliasLocalpartFromRoomName } from "../matrix-utils";
 import { useGroupCallRooms } from "./useGroupCallRooms";
 import { Header, HeaderLogo, LeftNav, RightNav } from "../Header";
@@ -26,28 +34,35 @@ import { CallList } from "./CallList";
 import { UserMenuContainer } from "../UserMenuContainer";
 import { useModalTriggerState } from "../Modal";
 import { JoinExistingCallModal } from "./JoinExistingCallModal";
-import { useHistory } from "react-router-dom";
 import { Title } from "../typography/Typography";
 import { Form } from "../form/Form";
 import { CallType, CallTypeDropdown } from "./CallTypeDropdown";
 
-export function RegisteredView({ client }) {
+interface Props {
+  client: MatrixClient;
+  isPasswordlessUser: boolean;
+}
+
+export function RegisteredView({ client, isPasswordlessUser }: Props) {
   const [callType, setCallType] = useState(CallType.Video);
   const [loading, setLoading] = useState(false);
-  const [error, setError] = useState();
+  const [error, setError] = useState<Error>();
   const history = useHistory();
-  const onSubmit = useCallback(
-    (e) => {
+  const { modalState, modalProps } = useModalTriggerState();
+
+  const onSubmit: FormEventHandler<HTMLFormElement> = useCallback(
+    (e: FormEvent) => {
       e.preventDefault();
-      const data = new FormData(e.target);
-      const roomName = data.get("callName");
-      const ptt = callType === CallType.Radio;
+      const data = new FormData(e.target as HTMLFormElement);
+      const roomNameData = data.get("callName");
+      const roomName = typeof roomNameData === "string" ? roomNameData : "";
+      // const ptt = callType === CallType.Radio;
 
       async function submit() {
         setError(undefined);
         setLoading(true);
 
-        const [roomIdOrAlias] = await createRoom(client, roomName, ptt);
+        const [roomIdOrAlias] = await createRoom(client, roomName);
 
         if (roomIdOrAlias) {
           history.push(`/room/${roomIdOrAlias}`);
@@ -64,17 +79,15 @@ export function RegisteredView({ client }) {
           console.error(error);
           setLoading(false);
           setError(error);
-          reset();
         }
       });
     },
-    [client, callType]
+    [client, history, modalState]
   );
 
   const recentRooms = useGroupCallRooms(client);
 
-  const { modalState, modalProps } = useModalTriggerState();
-  const [existingRoomId, setExistingRoomId] = useState();
+  const [existingRoomId, setExistingRoomId] = useState<string>();
   const onJoinExistingRoom = useCallback(() => {
     history.push(`/${existingRoomId}`);
   }, [history, existingRoomId]);
diff --git a/src/home/useGroupCallRooms.js b/src/home/useGroupCallRooms.ts
similarity index 72%
rename from src/home/useGroupCallRooms.js
rename to src/home/useGroupCallRooms.ts
index 4177a5fe..cf15a267 100644
--- a/src/home/useGroupCallRooms.js
+++ b/src/home/useGroupCallRooms.ts
@@ -14,11 +14,21 @@ See the License for the specific language governing permissions and
 limitations under the License.
 */
 
+import { GroupCall, MatrixClient, Room, RoomMember } from "matrix-js-sdk";
+import { GroupCallEventHandlerEvent } from "matrix-js-sdk/src/webrtc/groupCallEventHandler";
 import { useState, useEffect } from "react";
 
-const tsCache = {};
+export interface GroupCallRoom {
+  roomId: string;
+  roomName: string;
+  avatarUrl: string;
+  room: Room;
+  groupCall: GroupCall;
+  participants: RoomMember[];
+}
+const tsCache: { [index: string]: number } = {};
 
-function getLastTs(client, r) {
+function getLastTs(client: MatrixClient, r: Room) {
   if (tsCache[r.roomId]) {
     return tsCache[r.roomId];
   }
@@ -59,13 +69,13 @@ function getLastTs(client, r) {
   return ts;
 }
 
-function sortRooms(client, rooms) {
+function sortRooms(client: MatrixClient, rooms: Room[]): Room[] {
   return rooms.sort((a, b) => {
     return getLastTs(client, b) - getLastTs(client, a);
   });
 }
 
-export function useGroupCallRooms(client) {
+export function useGroupCallRooms(client: MatrixClient): GroupCallRoom[] {
   const [rooms, setRooms] = useState([]);
 
   useEffect(() => {
@@ -90,12 +100,15 @@ export function useGroupCallRooms(client) {
 
     updateRooms();
 
-    client.on("GroupCall.incoming", updateRooms);
-    client.on("GroupCall.participants", updateRooms);
+    client.on(GroupCallEventHandlerEvent.Incoming, updateRooms);
+    client.on(GroupCallEventHandlerEvent.Participants, updateRooms);
 
     return () => {
-      client.removeListener("GroupCall.incoming", updateRooms);
-      client.removeListener("GroupCall.participants", updateRooms);
+      client.removeListener(GroupCallEventHandlerEvent.Incoming, updateRooms);
+      client.removeListener(
+        GroupCallEventHandlerEvent.Participants,
+        updateRooms
+      );
     };
   }, [client]);