To find what version of the app you’re on:
1) Click your profile logo found on the top right corner.
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2) You will be able to see the version of the app you’re using.
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If you aren't using the latest version, there are two ways to update the app:
1) Go to the app store and click [Update]
In case you’re using an older version and don’t see this option, you’ll need to uninstall and re-install the app.
2) Accept in-app OTA updates
When you receive an OTA update and accept it, you’ll need to wait a few seconds for the app to update and restart on its own.