Best phone service for business in 2019

Editor's note: Looking for a Phone Service for your business? If you're looking for information to help you choose the one that's right for you, use the questionnaire below to have our partner site, BuyerZone, provide you with information from a variety of vendors for free:
The modern office has become increasingly digital, and the office phone service is no different. While once a desk might have been covered with a bank of phones, now employees can use their smartphones or mobile devices