You can add a contact to HubSpot manually, by logging an email, or by scanning a business card using the HubSpot Mobile App.
3 Ways to Add a Contact to HubSpot
Manually Add a Contact to HubSpot
- Navigate to Contacts

2. Click Create Contact in the upper right corner
3. In the Create Contact pop-up enter the contacts email and/or name
4. Entered additional contact information, then click Create Contact at the bottom of the pop-up
Add a Contact to HubSpot by Sending & Logging an Email
Any time you select log an email to HubSpot (via the HubSpot inbox plug-in), HubSpot will automatically log the email to the associated recipient's contact timeline -

If the recipient does not exist as a contact inside of HubSpot, they will be automatically created as a contact and the outgoing email will be logged to their contact timeline in HubSpot.

Add a Contact to HubSpot Using the Business Card Scanner in the HubSpot Mobile App
You can add a contact to HubSpot using the card scan functionality in the HubSpot mobile app - Read instructions on adding a contact to HubSpot using the app, here.