diff --git a/src/App.tsx b/src/App.tsx
index 81e011f432..2ecaf2d911 100644
--- a/src/App.tsx
+++ b/src/App.tsx
@@ -1,26 +1,482 @@
-/* eslint-disable max-len */
+/* eslint-disable jsx-a11y/label-has-associated-control */
 /* eslint-disable jsx-a11y/control-has-associated-label */
-import React from 'react';
+import React, { useEffect, useRef, useState } from 'react';
 import { UserWarning } from './UserWarning';
+import {
+  getTodos,
+  USER_ID,
+  deleteTodo,
+  addTodo,
+  completeTodo,
+  renameTodo,
+} from './api/todos';
+import { Todo } from './types/Todo';
+import classNames from 'classnames';
 
-const USER_ID = 0;
+enum Filter {
+  All = 'all',
+  Active = 'active',
+  Completed = 'completed',
+}
 
 export const App: React.FC = () => {
+  const [todos, setTodos] = useState<Todo[]>([]);
+  const [filter, setFilter] = useState(Filter.All);
+  const [errorMessage, setErrorMessage] = useState('');
+  const [loadingTodoId, setLoadingTodoId] = useState<number | null>(null);
+  const [newTodoTitle, setNewTodoTitle] = useState('');
+  const [tempTodo, setTempTodo] = useState<Todo | null>(null);
+  const [isAdding, setIsAdding] = useState(false);
+  const [editingTodoId, setEditingTodoId] = useState<number | null>(null);
+  const [editingTitle, setEditingTitle] = useState<string>('');
+
+  const activeCount = todos.filter(todo => todo.completed === false);
+  const completedTodos = todos.filter(todo => todo.completed);
+
+  const inputRef = useRef<HTMLInputElement>(null);
+
+  useEffect(() => {
+    getTodos()
+      .then(setTodos)
+      .catch(() => setErrorMessage('Unable to load todos'));
+  }, []);
+
+  useEffect(() => {
+    if (!isAdding && inputRef.current) {
+      inputRef.current.focus();
+    }
+  }, [isAdding]);
+
+  function filterTodos() {
+    switch (filter) {
+      case Filter.Active:
+        return todos.filter(todo => !todo.completed);
+      case Filter.Completed:
+        return todos.filter(todo => todo.completed);
+      case Filter.All:
+      default:
+        return todos;
+    }
+  }
+
+  const handleAddTodo = (e: React.FormEvent) => {
+    e.preventDefault();
+    const trimmedTitle = newTodoTitle.trim();
+
+    if (!trimmedTitle) {
+      setErrorMessage('Title should not be empty');
+
+      return;
+    }
+
+    const newTodo: Omit<Todo, 'id'> = {
+      title: trimmedTitle,
+      userId: USER_ID,
+      completed: false,
+    };
+
+    setTempTodo({ ...newTodo, id: 0 });
+
+    setIsAdding(true);
+    addTodo(newTodo)
+      .then(todoItem => {
+        setTodos(prevTodos => [...prevTodos, todoItem]);
+        setNewTodoTitle('');
+      })
+      .catch(() => {
+        setErrorMessage('Unable to add a todo');
+      })
+      .finally(() => {
+        setTempTodo(null);
+        setIsAdding(false);
+        inputRef.current?.focus();
+      });
+  };
+
+  const handleDeleteCompleted = () => {
+    const completedIds = completedTodos.map(todo => todo.id);
+
+    Promise.allSettled(completedIds.map(id => deleteTodo(id)))
+      .then(results => {
+        const failedDeletions = completedIds.filter(
+          (_, index) => results[index].status === 'rejected',
+        );
+
+        setTodos(currentTodos =>
+          currentTodos.filter(
+            todo =>
+              !completedIds.includes(todo.id) ||
+              failedDeletions.includes(todo.id),
+          ),
+        );
+
+        if (failedDeletions.length > 0) {
+          setErrorMessage('Unable to delete a todo');
+        }
+      })
+      .catch(() => {
+        setErrorMessage('Unable to delete a todo');
+      })
+      .finally(() => inputRef.current?.focus());
+  };
+
+  const handleDelete = (todoId: number) => {
+    setLoadingTodoId(todoId);
+    deleteTodo(todoId)
+      .then(() => {
+        setTodos(currentTodos =>
+          currentTodos.filter(todo => todo.id !== todoId),
+        );
+      })
+      .catch(() => {
+        setErrorMessage('Unable to delete a todo');
+      })
+      .finally(() => {
+        inputRef.current?.focus();
+        setLoadingTodoId(null);
+      });
+  };
+
+  const handleComplete = (todoId: number) => {
+    const currentTodo = todos.find(todo => todo.id === todoId);
+
+    if (!currentTodo) {
+      return;
+    }
+
+    const newCompletionState = !currentTodo.completed;
+
+    setLoadingTodoId(todoId);
+    completeTodo(todoId, newCompletionState)
+      .then(() => {
+        setTodos(prevTodos =>
+          prevTodos.map(todo =>
+            todo.id === todoId
+              ? { ...todo, completed: newCompletionState }
+              : todo,
+          ),
+        );
+      })
+      .catch(() => {
+        setErrorMessage('Unable to update a todo');
+      })
+      .finally(() => {
+        setLoadingTodoId(null);
+      });
+  };
+
+  const handleCompleteAll = () => {
+    const allCompleted = todos.every(todo => todo.completed);
+    const newCompletionState = !allCompleted;
+
+    const todosToUpdate = newCompletionState
+      ? todos.filter(todo => !todo.completed)
+      : todos;
+
+    const todoIdsToUpdate = todosToUpdate.map(todo => todo.id);
+
+    Promise.allSettled(
+      todoIdsToUpdate.map(id => completeTodo(id, newCompletionState)),
+    )
+      .then(results => {
+        const failedUpdates = todoIdsToUpdate.filter(
+          (_, index) => results[index].status === 'rejected',
+        );
+
+        setTodos(currentTodos =>
+          currentTodos.map(todo =>
+            todoIdsToUpdate.includes(todo.id)
+              ? { ...todo, completed: newCompletionState }
+              : todo,
+          ),
+        );
+
+        if (failedUpdates.length > 0) {
+          setErrorMessage('Unable to update todos');
+        }
+      })
+      .catch(() => {
+        setErrorMessage('Unable to update todos');
+      });
+  };
+
+  const filteredTodos = filterTodos();
+
+  useEffect(() => {
+    if (errorMessage) {
+      const timer = setTimeout(() => setErrorMessage(''), 3000);
+
+      return () => clearTimeout(timer);
+    }
+
+    return;
+  }, [errorMessage]);
+
   if (!USER_ID) {
     return <UserWarning />;
   }
 
+  const handleSaveEdit = (todoId: number) => {
+    const trimmedTitle = editingTitle.trim();
+
+    const currentTodo = todos.find(todo => todo.id === todoId);
+
+    if (currentTodo && trimmedTitle === currentTodo.title) {
+      setEditingTodoId(null);
+
+      return;
+    }
+
+    if (trimmedTitle === '') {
+      handleDelete(todoId);
+    } else {
+      setLoadingTodoId(todoId);
+
+      renameTodo(todoId, trimmedTitle)
+        .then(() => {
+          setTodos(prevTodos =>
+            prevTodos.map(todo =>
+              todo.id === todoId ? { ...todo, title: trimmedTitle } : todo,
+            ),
+          );
+          setEditingTodoId(null);
+        })
+        .catch(() => {
+          setErrorMessage('Unable to update a todo');
+        })
+        .finally(() => {
+          setLoadingTodoId(null);
+        });
+    }
+  };
+
+  const handleCancelEdit = () => {
+    setEditingTodoId(null);
+    setEditingTitle('');
+  };
+
+  const handleEditTodo = (todoId: number, title: string) => {
+    setEditingTodoId(todoId);
+    setEditingTitle(title);
+  };
+
   return (
-    <section className="section container">
-      <p className="title is-4">
-        Copy all you need from the prev task:
-        <br />
-        <a href="https://github.com/mate-academy/react_todo-app-add-and-delete#react-todo-app-add-and-delete">
-          React Todo App - Add and Delete
-        </a>
-      </p>
-
-      <p className="subtitle">Styles are already copied</p>
-    </section>
+    <div className="todoapp">
+      <h1 className="todoapp__title">todos</h1>
+
+      <div className="todoapp__content">
+        <header className="todoapp__header">
+          {/* this button should have `active` class only if all todos are completed */}
+          {todos.length > 0 && (
+            <button
+              onClick={handleCompleteAll}
+              type="button"
+              className={classNames(
+                'todoapp__toggle-all',
+                activeCount.length === 0 && 'active',
+              )}
+              data-cy="ToggleAllButton"
+            />
+          )}
+
+          {/* Add a todo on form submit */}
+          <form onSubmit={handleAddTodo}>
+            <input
+              ref={inputRef}
+              data-cy="NewTodoField"
+              type="text"
+              className="todoapp__new-todo"
+              placeholder="What needs to be done?"
+              value={newTodoTitle}
+              onChange={e => setNewTodoTitle(e.target.value)}
+              disabled={isAdding}
+              autoFocus
+            />
+          </form>
+        </header>
+
+        <section className="todoapp__main" data-cy="TodoList">
+          {filteredTodos.map(todo => (
+            <div
+              data-cy="Todo"
+              className={classNames('todo', todo.completed && 'completed')}
+              key={todo.id}
+            >
+              <label
+                className="todo__status-label"
+                onClick={() => handleComplete(todo.id)}
+              >
+                <input
+                  data-cy="TodoStatus"
+                  type="checkbox"
+                  className="todo__status"
+                  checked={todo.completed}
+                />
+              </label>
+              {editingTodoId === todo.id ? (
+                <>
+                  <form onSubmit={e => e.preventDefault()}>
+                    <input
+                      data-cy="TodoTitleField"
+                      type="text"
+                      className="todo__title-field"
+                      placeholder="Empty todo will be deleted"
+                      value={editingTitle}
+                      onChange={e => setEditingTitle(e.target.value)}
+                      onBlur={() => handleSaveEdit(todo.id)}
+                      onKeyUp={e => {
+                        if (e.key === 'Enter') {
+                          handleSaveEdit(todo.id);
+                        } else if (e.key === 'Escape') {
+                          handleCancelEdit();
+                        }
+                      }}
+                      autoFocus
+                    />
+                  </form>
+                  <div
+                    data-cy="TodoLoader"
+                    className={classNames(
+                      'modal',
+                      'overlay',
+                      loadingTodoId === todo.id && 'is-active',
+                    )}
+                  >
+                    <div
+                      className="modal-background
+                     has-background-white-ter"
+                    />
+                    <div className="loader" />
+                  </div>
+                </>
+              ) : (
+                <>
+                  <span
+                    data-cy="TodoTitle"
+                    className="todo__title"
+                    onDoubleClick={() => handleEditTodo(todo.id, todo.title)}
+                  >
+                    {todo.title}
+                  </span>
+
+                  {/* Remove button appears only on hover */}
+                  <button
+                    type="button"
+                    className="todo__remove"
+                    data-cy="TodoDelete"
+                    onClick={() => handleDelete(todo.id)}
+                  >
+                    ×
+                  </button>
+
+                  {/* overlay will cover the todo while it is being deleted or updated */}
+                  <div
+                    data-cy="TodoLoader"
+                    className={classNames(
+                      'modal',
+                      'overlay',
+                      loadingTodoId === todo.id && 'is-active',
+                    )}
+                  >
+                    <div
+                      className="modal-background
+                    has-background-white-ter"
+                    />
+                    <div className="loader" />
+                  </div>
+                </>
+              )}
+            </div>
+          ))}
+          {tempTodo && (
+            <div data-cy="Todo" className="todo">
+              <label className="todo__status-label">
+                <input type="checkbox" className="todo__status" disabled />
+              </label>
+              <span data-cy="TodoTitle" className="todo__title">
+                {tempTodo.title}
+              </span>
+              <div data-cy="TodoLoader" className={'modal overlay is-active'}>
+                <div className="modal-background has-background-white-ter" />
+                <div className="loader" />
+              </div>
+            </div>
+          )}
+        </section>
+
+        {/* Hide the footer if there are no todos */}
+        {todos.length > 0 && (
+          <footer className="todoapp__footer" data-cy="Footer">
+            <span className="todo-count" data-cy="TodosCounter">
+              {activeCount.length} items left
+            </span>
+
+            {/* Active link should have the 'selected' class */}
+            <nav className="filter" data-cy="Filter">
+              <a
+                href="#/"
+                className={classNames(
+                  'filter__link',
+                  filter === Filter.All && 'selected',
+                )}
+                data-cy="FilterLinkAll"
+                onClick={() => setFilter(Filter.All)}
+              >
+                All
+              </a>
+
+              <a
+                href="#/active"
+                className={
+                  filter === Filter.Active
+                    ? 'filter__link selected'
+                    : 'filter__link'
+                }
+                data-cy="FilterLinkActive"
+                onClick={() => setFilter(Filter.Active)}
+              >
+                Active
+              </a>
+
+              <a
+                href="#/completed"
+                className={
+                  filter === 'completed'
+                    ? 'filter__link selected'
+                    : 'filter__link'
+                }
+                data-cy="FilterLinkCompleted"
+                onClick={() => setFilter(Filter.Completed)}
+              >
+                Completed
+              </a>
+            </nav>
+
+            {/* this button should be disabled if there are no completed todos */}
+            <button
+              type="button"
+              className="todoapp__clear-completed"
+              data-cy="ClearCompletedButton"
+              onClick={() => handleDeleteCompleted()}
+              disabled={!completedTodos.length}
+            >
+              Clear completed
+            </button>
+          </footer>
+        )}
+      </div>
+
+      <div
+        data-cy="ErrorNotification"
+        className={
+          errorMessage
+            ? 'notification is-danger is-light has-text-weight-normal'
+            : 'hidden'
+        }
+      >
+        <button data-cy="HideErrorButton" type="button" className="delete" />
+        {errorMessage}
+      </div>
+    </div>
   );
 };
diff --git a/src/api/todos.ts b/src/api/todos.ts
new file mode 100644
index 0000000000..697a2987f2
--- /dev/null
+++ b/src/api/todos.ts
@@ -0,0 +1,36 @@
+import { Todo } from '../types/Todo';
+import { client } from '../utils/fetchClient';
+
+export const USER_ID = 2129;
+
+export const getTodos = () => {
+  const baseUrl = `/todos?userId=${USER_ID}`;
+
+  return client.get<Todo[]>(baseUrl);
+};
+
+export const deleteTodo = (id: number) => {
+  const baseUrl = `/todos/${id}`;
+
+  return client.delete(baseUrl);
+};
+
+export const addTodo = (newTodo: Omit<Todo, 'id'>) => {
+  const baseUrl = `/todos`;
+
+  return client.post<Todo>(baseUrl, newTodo);
+};
+
+export const completeTodo = (id: number, completed: boolean) => {
+  const baseUrl = `/todos/${id}`;
+
+  return client.patch(baseUrl, { completed });
+};
+
+export const renameTodo = (id: number, title: string) => {
+  const baseUrl = `/todos/${id}`;
+
+  return client.patch(baseUrl, { title: title });
+};
+
+// Add more methods here
diff --git a/src/styles/index.scss b/src/styles/index.scss
index bccd80c8bc..35583d0c4a 100644
--- a/src/styles/index.scss
+++ b/src/styles/index.scss
@@ -20,6 +20,10 @@ body {
   pointer-events: none;
 }
 
+.hidden {
+  display: none
+}
+
 @import "./todoapp";
 @import "./todo";
 @import "./filter";
diff --git a/src/styles/todoapp.scss b/src/styles/todoapp.scss
index ad28bcb2fe..27b57251a4 100644
--- a/src/styles/todoapp.scss
+++ b/src/styles/todoapp.scss
@@ -1,4 +1,3 @@
-
 .todoapp {
   font-family: "Helvetica Neue", Helvetica, Arial, sans-serif;
   font-size: 24px;
@@ -69,7 +68,7 @@
 
     border: none;
     background: rgba(0, 0, 0, 0.01);
-    box-shadow: inset 0 -2px 1px rgba(0,0,0,0.03);
+    box-shadow: inset 0 -2px 1px rgba(0, 0, 0, 0.03);
 
     &::placeholder {
       font-style: italic;
diff --git a/src/types/Todo.ts b/src/types/Todo.ts
new file mode 100644
index 0000000000..3f52a5fdde
--- /dev/null
+++ b/src/types/Todo.ts
@@ -0,0 +1,6 @@
+export interface Todo {
+  id: number;
+  userId: number;
+  title: string;
+  completed: boolean;
+}
diff --git a/src/utils/fetchClient.ts b/src/utils/fetchClient.ts
new file mode 100644
index 0000000000..708ac4c17b
--- /dev/null
+++ b/src/utils/fetchClient.ts
@@ -0,0 +1,46 @@
+/* eslint-disable @typescript-eslint/no-explicit-any */
+const BASE_URL = 'https://mate.academy/students-api';
+
+// returns a promise resolved after a given delay
+function wait(delay: number) {
+  return new Promise(resolve => {
+    setTimeout(resolve, delay);
+  });
+}
+
+// To have autocompletion and avoid mistypes
+type RequestMethod = 'GET' | 'POST' | 'PATCH' | 'DELETE';
+
+function request<T>(
+  url: string,
+  method: RequestMethod = 'GET',
+  data: any = null, // we can send any data to the server
+): Promise<T> {
+  const options: RequestInit = { method };
+
+  if (data) {
+    // We add body and Content-Type only for the requests with data
+    options.body = JSON.stringify(data);
+    options.headers = {
+      'Content-Type': 'application/json; charset=UTF-8',
+    };
+  }
+
+  // DON'T change the delay it is required for tests
+  return wait(100)
+    .then(() => fetch(BASE_URL + url, options))
+    .then(response => {
+      if (!response.ok) {
+        throw new Error();
+      }
+
+      return response.json();
+    });
+}
+
+export const client = {
+  get: <T>(url: string) => request<T>(url),
+  post: <T>(url: string, data: any) => request<T>(url, 'POST', data),
+  patch: <T>(url: string, data: any) => request<T>(url, 'PATCH', data),
+  delete: (url: string) => request(url, 'DELETE'),
+};