ASK IH : How do you follow up your emails.

Hello community,

After google gmail "nudge" feature and me asking gmail support "is there a search command that help me see mails without answer" and recieveing a negative,i got to ask :

In the following context :

• regular gmail client (no automation, no prospect.io & al)
• email that you have send and "hope to get an answer in the next couple days"
• can be commercial or not (ex : question to landlord)

How to you track those mails ?

Gmail Nudge (https://twitter.com/gmail/status/994601210303918082?s=20) feature is pretty slick but no control on it, and documenation explicitly says "When Gmail thinks its usefull".
I'm thinking about doing some gmail api custom app for me, but i wanted to ask before investing those hours :)

Cheers !