Choose which labels you want to filter and tap Done to apply your filter.
Label changes from other devices
To see changes of labels in this filter menu that were made on another device go to the project page and re-open the project.
Similarly you will not be able to see a new external label until the project is reloaded.
Reset label icon
You can click on the reset button on the top left to deselect all selected labels.
(P.S. If you want cool emojis in your filters you can easily do this by changing label names in the mobile browser version of Catenda Hub)