It’s been possible on the web for quite a while, but a recent update to the Google Keep app now lets you quickly export your notes to a Google Doc. To do so, make sure you have the latest version of the app, and then select the notes you’d like to export. Then tap the drop down menu at the top right of the screen and tap “Copy to Google Doc”. It’s pretty nifty.
You can grab the app from the Play Store for free of course, and if you’d like to try out the feature right now, open this page on your Android device. All you have to do is tap below to download the APK (via APKMirror), and then tap the notification on your phone once the app is done downloading. You’ll be walked through a couple steps, and then you’ll be on the latest version.