I built this tool during the last league and decided to open source it since we just started this new league. It is just a native interface for saved searches. It uses the same functionality you can get from the trade website by tracking searches via web sockets. But rather than having multiple tabs, it is in a native interface and saves the searches to local storage.
It even implements the 'tap to travel' functionality!
The downside is the setup is kind of technical (have to inspect the console to grab your token), and adding searches is done via pasting JSON. I usually just do a search, then look at the network requests and grab the JSON that way.
I might try to figure out a better way, but meh, it works.