Google has been bringing changes to several of its apps like Photos, Gmail, Maps, etc lately. Smooth gesture to switch accounts was added to Maps, Gmail, etc and on similar lines now, Google has started rolling out Material Theme account switcher for the Play Store and this comes after a revamp last year.
With the latest Play Store update, the top right part shows the user’s profile image and tapping the profile image opens up a full menu that displays the Google accounts present on the device and it also lets you add another account and manage accounts. Similar to Gmail, a quick swipe down gesture on the profile image allows you to quickly switch accounts.
Furthermore, thanks to the change in the position of account switcher, the navigation bar is now shorter. However, the design switch does not make it fully material as the settings and account information can be managed only via the navigation bar, still.
The update is rolling out gradually to devices that are on version 19.3 and higher. If you are not seeing the update right away, you should wait until the rollout is complete or if you are not willing to wait, you can enable it manually by clearing the Storage and cache of Google Play Store→Open the app→Close it again from the multitasking menu. After following these steps, the material account switcher should appear.