Blizzard have taken to their forums recently to announce that they'll be cracking down on any and all third-party software that may provide unfair advantages in Overwatch and the first two victims seem to be Visor.gg and Pursuit apps.
The company wrote that any "third-party application that offers users information such as enemy position, enemy health, enemy ability usage, or Ultimate readiness creates an uneven playing field for every other player". These apps are in direct violation of Blizzard's EULA, which is pretty clear on anything cheat, bot or hack related.
Unlike with regular cheaters though, Overwatch players who are using such applications will be warned by Blizzard in the following days, if they haven't been already. There will be no retroactive bans or anything, which is good news for players using it, some of which are said to be prominent Overwatch community members.
Unfortunately for Blizzard and Overwatch, there seems to be plenty of confusion over some apps, most notably Pursuit, because it doesn't seem to fit into the blanket statement via which the company announced the crackdown. Some players have already raised the issues on the forums but, as it tends to be the case with Blizzard, they don't seem to visit that neck of the woods for feedback - only announcements.
What Pursuit does is a statistics analysis of your Overwatch matches, which you can later use to improve your game, much like if you simply record matches and got tutoring from more experienced players. The app features no automation of any sort, nor does it notify you of enemy health or anything of the sort.
The irony of it all is that Pursuit is endorsed by Philadelphia Fusion, this year's OWL finalists and Angry Titans, EU's OWL contenders. The list goes on, because Pursuit was also used by six Overwatch World Cup 2018 teams - Canada, Australia, Italy, Netherlands, Norway and France.
Visor.gg, on the other hand, seems to be a more proactive app in that it has all sorts of in-game notifications that may ultimately provide you with an unfair upper hand. This app has apparently been used by the aforementioned prominent Overwatch community members but we'll refrain from naming anyone until we can properly investigate.
You can find Blizzard's statement here.