As user experience improvement we can always show a star icon to one side of the bus stop name.

The star icon should be full when the bus stop is in the favorites and outline otherwise.

— from Launchpad

Actually the user experience is very poor because an user have to know that tapping on a Stop Name add it to the favorites. I think this is actually suitable only for a post in the SoftwareGore subreddit.

These are the key points:

1. Add a Stop in the favorites should be intuitive
2. Checking if that Stop is already in the favorites should be somehow clear

This is the actual feel:

Possible available space for an "Add to favorite" button:

M7 Libre BusTO Favourites

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