Take your smartphone to a higher level with Ooma Office for Mobile, a cloud-based enterprise phone service app that lets you run your business from anywhere. Available on iOS and Google Play, Office for Mobile gives you a virtual receptionist, music on hold, conferencing, toll-free numbers, and 24/7 support for your customers. Cost for these features, plus unlimited calling in the U.S. and Canada: $19.95/month after a 30-day free trial.