Cobalt
🌍
The app that summarizes your books

Take back control of your book pile.

Over 500 non-fiction book summaries, in 5 minutes. In text or audio. Everything that matters, without the filler.

Download on the App Store Get it on Google Play

7 days free · iOS + Android

What our users say

Busy readers who rediscovered the joy of learning.

I use the app every day on public transport. It's fast and really well made. It's become my main tool for continuous learning.

Benoit R.

Exactly what I was looking for! The key concepts are perfect. Being able to adjust the depth of the summaries to my mood — what an incredible comfort.

Hugo T.

The concept is brilliant, like Koober but updated and personalized! I wrote to the team about a feature, 10 hours later it was added on a public holiday — I couldn't believe it! 😳🤩

Lyrie630..

Great app to get the essence of a book in a few minutes. I love the summaries by key concept. Honestly, it's really worth it!

Alice G.