Docsify allows you to track multiple emails simultaneously.
Some of the insights you can gain in real-time from the per-recipient email tracking feature are:
who opened your email
how many times your email was opened
how many times inserted links were opened
how many times inserted attachments were downloaded
what devices it was opened from
Emails are not the only things you can track using Docsify. Using the per-recipient per-page document tracking feature you can also assess the level of engagement recipients have had with documents you have shared.
Here's a 2 min overview video: https://www.youtube.com/watch?time_continue=3&v=lZqCdSEOp7E