Google plans to bring back its Google Notebook, giving it a new avatar and a new branding--now calling it "Google Keep."
Recently, while digging through Google Drive source code, Carlos Jeurissen found some interesting hints about the new unreleased Google Drive app "Google Keep."
There are multiple references to Google Keep in the Google Drive code, including some URLs like: https://drive.google.com/keep/?note. In fact, the codename for Google Keep is "memento" and the MIME type for Google Keep files is "application/vnd.google-apps.note".
In addition, Carlos also found the service's icon, a folder icon, and a short URL http://g.co/keep that redirects to the Play Store page https://play.google.com/store/apps/details?id=com.google.android.keep for a non-existent Google Keep app--and hints Keep will probably get it's own Google Play store app.
Additionally, a new Google Account Service named "Portal" was also discovered at https://accounts.google.com/servicelogin?service=portal.
"When you signed in to that, it added a new Google Keep service in www.google.com/settings/products," mentions Carlos. It is removed now, including the Service which means a possible release is nearby.
Since, Google sometimes tests new products on the sandbox.google.com domain, "check on https://drive.sandbox.google.com/keep/--redirects to https://drive.sandbox.google.com/notes/. And, it has the same looking favicon as the icon uploaded to the Google products icon folder: http://www.gstatic.com/docs/notes/keep.ico."
For now, Google has a cool Chrome extension "Scratchpad," and it is great for taking notes and it syncs with Google Docs.