* Google Books offers a large selection of free and paid ebooks. You can search for books by title, author, or ISBN, and read them online or download them to your device.
* Amazon Kindle is an online store where you can buy and read ebooks. You can also subscribe to Kindle Unlimited, which gives you access to a library of over 1 million ebooks for a monthly fee.
* Barnes & Noble Nook is another online store where you can buy and read ebooks. You can also subscribe to Nook Bookshelf, which gives you access to a library of over 1 million ebooks for a monthly fee.
* Kobo is an online store where you can buy and read ebooks. You can also subscribe to Kobo Plus, which gives you access to a library of over 1 million ebooks for a monthly fee.