Can I send an email to multiple SharePoint list contacts at once?

Yes, JungleMail for Office 365 allows you to send group emails to multiple selected items in your SharePoint Online list, as well as to list views or entire SharePoint lists. If you open the app from a SharePoint list via the top menu bar, that list will be selected automatically as a recipient source. You can click the Browse button and specify a different list, specify additional recipients, apply filters, and more. See Recipient sources.