This is the proposal for the project idea shared on OSM wiki page https://wiki.openstreetmap.org/wiki/Google_Summer_of_Code/2017/Project_Ideas
"Suggested By - Zverik
To increase a number of public transport routes in OSM, we need a simple to use web-based editor. It would need to download stops and route relations, edit tags and relation members, keep nodes connected to ways, know about stop positions and platforms. See this write-up. The criteria for finished work will be a functioning and error-free web editor for stops and route relations. Way editing is not required (though it would be an interesting problem).
Difficulty - Medium
Possible Mentors - Zverik