This Googlebook app just leaked in its entirety, and you can already try it on your phone

TL;DR Google briefly released an upcoming Googlebook app called Look up, before scrubbing all references from the Play Store listing. While users can no longer download it directly from the Play Store, the app can be sideloaded on phones running Android 17. In addition to instantly answering questions based on the highlighted text, Look up also features a conventional chatbot experience for additional questions.