It usually is best to just make a call to gather information. Don’t get discouraged if you do not have success on your first call into a business. It usually takes a number of follow ups to get to the DM and to set up a meeting with them. When you do get the DM on the phone tell them why your app will benefit them and ask for a meeting to go into more detail. Typically, you will never close a sale on the first... Source: almost 3 years ago

You can use the free plan at Symbo.ai to manage your communication through sequences. You can send manual and automated emails which will help you say in communication with your leads, buyers, and investors. It will even sync up to your Salesforce or HubSpot to make your life easier! Source: almost 3 years ago

I'll update this if I find more. For now, this seems to be a partial solution. It's a Gmail add on (except I don't use Gmail) that adds reminders. The options when setting reminders include cancelling it if someone replies, and to remind everyone in the thread. If you combine those two, it seems like — if you use Gmail's web client and have $23/month you're dying to get rid of — a decent way to add the feature. Source: over 1 year ago