Simple notifications triggered by admin

Hello,

I have been looking for a plugin to send simple notifications to a group of subscribers to let them know about a new content. Most of the plugins out there do this, however they send notifications for new posts etc.

I would like a plugin, in which I could have some templates and I could just press one button to send the same notification whenever I update some tables with data.

Could you please recommend me a solution that would do this?
I’m looking for either email notifications or mobile notifications.

Thank you