DC Rainmaker has these points, is essence, third party apps can only display your data back to you, that's it. They can't add any value and can't share or aggregate (such as to coaches or leaderboards). From DCR...
#1: “Third-party apps are no longer able to display your Strava activity data on their surfaces to other users.”
#2: “We’re updating our terms to explicitly prohibit third parties from using any data obtained via Strava’s API in artificial intelligence models or other similar applications.”
#3: “You may not process or disclose Strava Data…for the purposes of, including but not limited to, analytics, analyses…”
