Google Voice - Google Voice gives you one number for all your phones, voicemail organized in an email format, free...
Ring4 - Manage business phone line as easily as you manage emails, in the cloud. Ring4 provide you with a business line and video conferencing solution.
Visible - Visible is a wireless service by Verizon that offers unlimited data for a small price and enables you to earn a few bucks by referring friends.
SpotMenu - Spotify and iTunes in your macOS menu bar
Fonoster - A marketplace where local telecom companies can publish numbers, developers can build voice, video, and chat solutions.
OpenPhone - Simplest way to own a business phone number