diff --git a/TODO.md b/TODO.md
index e04e18d..8e73f6c 100644
--- a/TODO.md
+++ b/TODO.md
@@ -1,6 +1,5 @@
 Only immediate next things to do are listed here, without any far-fetching plans.
 
-- Implement syncing local storage with service worker (either via postMessage or using IndexedDB)
 - Implement reminders
 - Implement masonry layout
 - Implement color coding
diff --git a/js/db-store.js b/js/db-store.js
new file mode 100644
index 0000000..7fdeda6
--- /dev/null
+++ b/js/db-store.js
@@ -0,0 +1,139 @@
+export class DBNoteStore extends EventTarget {
+  constructor(dbName, storeName) {
+    super();
+    this.dbName = dbName;
+    this.storeName = storeName;
+    this.db = null;
+  }
+
+  async all() {
+    const that = this;
+    return this.#connect().then(
+      (db) =>
+        new Promise((resolve, reject) => {
+          db
+            .transaction([that.storeName], "readonly")
+            .objectStore(that.storeName)
+            .getAll().onsuccess = (data) => resolve(data.target.result);
+        }),
+    );
+  }
+
+  async get(id) {
+    const that = this;
+    let result;
+
+    return this.#connect().then(
+      (db) =>
+        new Promise(
+          (resolve, reject) =>
+            (db
+              .transaction([that.storeName], "readonly")
+              .objectStore(that.storeName)
+              .get(id).onsuccess = (data) => resolve(data.target.result)),
+        ),
+    );
+  }
+
+  async add(note) {
+    const that = this;
+
+    const entry = {
+      id: "id_" + Date.now(),
+      type: note.type,
+      content: note.content,
+      created: new Date(),
+    };
+
+    return this.#connect().then(
+      (db) =>
+        new Promise(
+          (resolve, reject) =>
+            (db
+              .transaction([that.storeName], "readwrite")
+              .objectStore(that.storeName)
+              .add(entry).onsuccess = () => resolve(null)),
+        ),
+    );
+  }
+
+  async reset() {
+    const that = this;
+
+    return this.#connect().then(
+      (db) =>
+        new Promise(
+          (resolve, reject) =>
+            (db
+              .transaction([that.storeName], "readwrite")
+              .objectStore(that.storeName)
+              .clear().onsuccess = () => resolve(null)),
+        ),
+    );
+  }
+
+  async remove({ id }) {
+    const that = this;
+
+    return this.#connect().then(
+      (db) =>
+        new Promise(
+          (resolve, reject) =>
+            (db
+              .transaction([that.storeName], "readwrite")
+              .objectStore(that.storeName)
+              .delete(id).onsuccess = () => resolve(null)),
+        ),
+    );
+  }
+
+  async update(note) {
+    const that = this;
+
+    return this.#connect().then(
+      (db) =>
+        new Promise(
+          (resolve, reject) =>
+            (db
+              .transaction([that.storeName], "readwrite")
+              .objectStore(that.storeName)
+              .put(note).onsuccess = () => resolve(null)),
+        ),
+    );
+  }
+
+  saveStorage() {
+    this.dispatchEvent(new CustomEvent("save"));
+  }
+
+  async #connect() {
+    if (!this.db) {
+      this.db = await this.#dbConnect();
+    }
+
+    return this.db;
+  }
+
+  #dbConnect() {
+    const that = this;
+
+    return new Promise((resolve, reject) => {
+      const request = indexedDB.open(this.dbName, 1);
+
+      request.onsuccess = (e) => {
+        resolve(e.target.result);
+      };
+
+      request.onerror = (e) => {
+        console.error(`indexedDB error: ${e.target.errorCode}`);
+      };
+
+      request.onupgradeneeded = (e) => {
+        const db = e.target.result;
+        db.createObjectStore(that.storeName, {
+          keyPath: "id",
+        });
+      };
+    });
+  }
+}
diff --git a/js/jenot.js b/js/jenot.js
index 1a8c813..f080690 100644
--- a/js/jenot.js
+++ b/js/jenot.js
@@ -1,9 +1,14 @@
 import "./service-worker.js";
 import { renderText } from "./dom.js";
 import { NoteStore } from "./store.js";
+import { DBNoteStore } from "./db-store.js";
 import "./components.js";
 
-const Notes = new NoteStore("jenot-app");
+const urlParams = new URLSearchParams(window.location.search);
+
+const Notes = urlParams.has("localStorage")
+  ? new NoteStore("jenot-app")
+  : new DBNoteStore("jenot-app", "notes");
 
 const newNote = document.querySelector("#new-note");
 const editNote = document.querySelector("#edit-note");
@@ -12,28 +17,27 @@ Notes.addEventListener("save", render.bind(this));
 
 render();
 
-newNote.addEventListener("addNote", (e) => {
-  console.log(e.detail);
-  Notes.add(e.detail);
+newNote.addEventListener("addNote", async (e) => {
+  await Notes.add(e.detail);
   Notes.saveStorage();
 });
 
-editNote.addEventListener("updateNote", (e) => {
+editNote.addEventListener("updateNote", async (e) => {
   newNote.classList.remove("hidden");
   editNote.classList.add("hidden");
-  Notes.update(e.detail);
+  await Notes.update(e.detail);
   Notes.saveStorage();
 });
 
-editNote.addEventListener("deleteNote", (e) => {
+editNote.addEventListener("deleteNote", async (e) => {
   newNote.classList.remove("hidden");
   editNote.classList.add("hidden");
-  Notes.remove(e.detail);
+  await Notes.remove(e.detail);
   Notes.saveStorage();
 });
 
-function render() {
-  const notes = Notes.all();
+async function render() {
+  const notes = await Notes.all();
   const notesContainer = document.querySelector("#notes");
   notesContainer.replaceChildren();
 
@@ -64,10 +68,11 @@ function render() {
 
     notesContainer.appendChild(container);
 
-    container.addEventListener("click", (e) => {
+    container.addEventListener("click", async (e) => {
       newNote.classList.add("hidden");
       editNote.classList.remove("hidden");
-      editNote.load(Notes.get(container.id));
+      const note = await Notes.get(container.id);
+      editNote.load(note);
     });
   });
 }
diff --git a/js/store.js b/js/store.js
index 343fcdf..8fb440f 100644
--- a/js/store.js
+++ b/js/store.js
@@ -1,7 +1,6 @@
 export class NoteStore extends EventTarget {
   localStorageKey;
   notes = [];
-  editedNoteId = "none";
 
   /*
   Note structure:
@@ -31,7 +30,6 @@ export class NoteStore extends EventTarget {
 
   all = () => this.notes;
   get = (id) => this.notes.find((note) => note.id === id);
-  getEditedNoteId = () => this.editedNoteId;
 
   add(note) {
     this.notes.unshift({
@@ -54,19 +52,11 @@ export class NoteStore extends EventTarget {
     this.notes = this.notes.map((n) => (n.id === note.id ? note : n));
   }
 
-  setEditedNoteId(id) {
-    this.editedNoteId = id;
-  }
-
   saveStorage() {
     window.localStorage.setItem(
       this.localStorageKey + "_notes",
       JSON.stringify(this.notes),
     );
-    window.localStorage.setItem(
-      this.localStorageKey + "_editedNoteId",
-      this.editedNoteId,
-    );
     this.dispatchEvent(new CustomEvent("save"));
   }
 
@@ -74,8 +64,5 @@ export class NoteStore extends EventTarget {
     this.notes = JSON.parse(
       window.localStorage.getItem(this.localStorageKey + "_notes") || "[]",
     );
-    this.editedNoteId =
-      window.localStorage.getItem(this.localStorageKey + "_editedNoteId") ||
-      "none";
   }
 }