Integration with Apple HealthKit would allow btwb to pull weight, sleep and other data automatically without needing to manually log in multiple locations.
Integration with Strava (and/or Garmin) to import running, cycling and swimming workouts directly into btwb to avoid needing to manually input workouts.
Honestly, for a paid subscription fitness app, I expected these features to be included already.
Seriously, how is this not a feature at this point in time? But after viewing the stack used to build btwb, it actually makes sense as to why Apple Health integration hasn't been developed yet. Time to get rid of the legacy code and rebuild/update the platform.