Possibly because it’s a bit of a cludge. Activity needs to sync from watch to Fitbit. Then sync from Fitbit to Strava, where Strava does its bit. Then sync from Strava back to Fitbit. Then sync from Fitbit back to your watch, where all you can do is just view it. But the slowness might be down to how often / well your watch and phone sync. Either way, Strava on the Ionic is of debatable benefit.
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