What hardware devices are essential for using VoIP?
For individual use, I guess it is obvious that you’ll need a telephone set so you can receive and make calls. When calling via the Internet, a pair of quality headsets come in handy. You can choose some that best suit PCs or laptops, or headsets designed for mobile devices like tablet PCs. Go for the headphones with the highest sound quality.
When you’re using VoIP only at home, your smartphone, pc or tablet with headphones, and of course the internet connection is all you need. However, when you get VoIP for a small business, you’ll also need an IP phone and a business VoIP provider.
If you use the existing phones in the office you will need analog telephone adapters that will come as interface between analog PSTN phone and digital VoIP line.