Show HN: Curated Real-News on Topics You Follow

1) Google News Alerts: limited to Google, will send fake news, I have some other really strange examples. No sentiment attached and sends notifications based on non-obvious rules. Lettergram.net can be configured to send on sentiment changes, trend changes, or on a schedule.

2) Can't modify the sources, the system actually has no concept of a "source". However, you can modify the topics you follow.

3) Yes, you can modify it to be real-time, based on sentiment or volume of discussion changes. OR you can set it to be time interval based.