Big thing people are leaving out here. FFXIVAPP and ACT are more than just parsers. Using it as just a parser is fine, just don't grief another player over his/her DPS, although there are ways to determine if a player is doing well or not without one.

Using these applications with their trigger commands is illegal. Can see it in DnT's T13 kill, as well as many other videos from back in the first coil when they are used to call out Twisters. At this point, the application is doing some of the work for you.