Read and listen, in sync. Questions about Tandem? We're here to help.
Email us at support@tandembooks.co. We aim to respond within 2 business days.
Tandem is an app for switching between an ebook and its audiobook without losing your place. Import a DRM-free EPUB, pair it with a matching M4B or MP3, and move between reading and listening in one app.
Tandem reads EPUB ebook files and plays M4B or MP3 audiobooks. Import your files using the + menu in the library.
Import both files. Tandem will try to match them when the title and author look right, or you can pair them manually from the book's menu.
When you switch modes, Tandem uses a short audio check to place you in the matching part of the book, then keeps the ebook and audiobook aligned as you continue. The first handoff in a chapter can take a few seconds, and later switches in the same area are faster because Tandem remembers that position on your device.
On iOS, this permission allows Tandem to optionally use Apple's on-device transcription for sync instead of the cloud service. Your microphone is never recorded.
Reading and listening work offline. Finding your place during a fresh ebook-to-audiobook handoff can require a short internet request to analyze a small piece of audio. Once Tandem has matched that area, it remembers the result on your device.
Web (any modern browser at tandembooks.co/app), iOS 26, iPadOS 26, macOS 26, and visionOS 26. The native app is universal — one purchase, all four Apple platforms.
No. Tandem works fully without an account. Your books, reading progress, and highlights are stored locally on your device. If you want to sync across devices or prepare for book clubs, you can optionally sign in.
When signed in, your reading progress and highlights sync to the cloud so they're available on all your devices. Your book files never leave your device. You can delete your account and all synced data at any time from the app.
Yes. Go to the account screen in the app and tap 'Delete Account.' This permanently removes your account and all synced data from our servers. Local data on your device is not affected.
Email support@tandembooks.co with details. For bugs, please include what you were doing and which book you were reading.
See our privacy policy for details on what data Tandem stores and how it's used.