This article explains how to change a playlist picture on Spotify on your Android device. Previously, Spotify required you to use the desktop app to change playlist cover images, but that is no longer the case. You can use any image stored on your Android device as your Spotify playlist picture, or take a new photo with your device's built-in camera and use that instead. You can also change your main Spotify picture or profile picture via the Android app.
How to change Spotify playlist picture on your phone?
The Android Spotify app lets you change the cover photo for any of your playlists using the Android app, so you don’t have to load the app onto a computer to perform this task. When changing a Spotify playlist photo on your mobile, you can select any image currently stored on your device, or take a new photo using one of the cameras built into your device.
When you change a playlist image on the Spotify mobile app, it will automatically change on all your other devices. You don't need to change it again on the desktop app or any of your other devices.
Here's how to change the cover image of a playlist in Spotify on Android: