With the fierce competition and the growing demand in the design market, the prototype software developers have resorted to their effort to meet the different user requirement. They launched a series of product service versions, such as free version, professional version, and the perpetual license version. Most of the UI/UX designers may have been familiar with the free version and pro version, but know little about the perpetual license. This article will introduce you about the perpetual license about four prototyping tools. 1. Axure RP Axure has launched three versions: Pro, Team, and Enterprise . But the support for the perpetual license, that is limited to users who have already purchased the Professional or Team Edition. In the Axure RP 8.0 version, users can purchase license key at the price of $ 495 and $ 895. Moreover, once you purchased the perpetual license, you can have the software update for free in your lifetime. (Get the license here: https://www...