I installed protractor following this tutorial and when i use webdriver-manager update it says:
selenium standalone is up to date. chromedriver is up to date. >
After looking around for a while, I noticed that the package.json file included in the angular phonecat repo defines a update-webdriver task.
package.json
update-webdriver
Running that task (with npm run update-webdriver) fixed protractor for me.
npm run update-webdriver