Figma - Team-based interface design, Figma lets you collaborate on designs in real time.
Email Verification on Google Sheets - An add-on for email verification directly in Google Sheets
Invision - Prototyping and collaboration for design teams
Verifier - Weed out disposable, non-existent domains or invalid emails.
Sketch - Professional digital design for Mac.
Clearbit Salesforce Prospector - Quickly build targeted lead lists directly in Salesforce