1. Look out for a pop up on the upper right corner, with a button saying "update app"
2. Click the button to go to the download site and click on 'Download Update', then follow the process
3. Alternatively, go to the app download link and follow the process.
Please check Here to update
pop up a blue button at the top saying "Update app" and clicking it will lead to the update process.
Don't worry about it, the app on your phone updates automatically.