eezyCollab

This app is great for finding influencers in your niche. Not sure if it pulls from live search or database. But I found popular people in my niche. You can filter search results by followers and engagement. Soon you'll be able to filter by keywords, which they say is in development. You can setup your gmail or smtp email service to send bulk outreach emails to influencers.

I'm using it to find collaborators and research what's happening in my niches.