What CRM do you use?

Our product is starting to get traction, and we (co-founder and myself) are receiving more communications than we're used to.

Challenges we're facing:

- High volume of messages, that keeps growing

- Various channels: personal/brand emails, contact form, LinkedIn

- No efficient workflow to share comments about the messages, eg we forward emails to each other with some notes but that's not scalable

I believe a CRM tool would help us, but I'm not sure what to choose.

I hear Hubspot is a popular choice, but it doesn't look like it handles LinkedIn incoming messages out of the box, which is a must for us.