Zoiper: 3.5

: Supports core business tasks such as call transfer (attended and blind), conferencing, call recording, and instant messaging. Encryption & Security

The UI in 3.5 was clean and functional: a numeric keypad, contact list, call history, and status indicator. It lacked the modern "chat-first" design but excelled at being a phone . Skinning support allowed users to change the look and feel. zoiper 3.5