Even if you use your mobile phone for the majority of your business needs, it's smart to have a landline as backup in case your service drops or you lose your device. It's also simply higher quality audio than you smartphone, making it easier to conduct meetings without either party misunderstanding the other. You can even get a VoIP phone or get an online number, like those offered through Google or Skype. Some of these VoIP services even offer features like voicemail transcription, SMS messaging, group calls, call recording, call routing and more. You'll want to consider your personal needs to make sure you sign up for the right service.