Bimx and bimx pro are really a good products, but they work on a one way workflow, data cannot be returned back from bimx to archicad after a meeting,
In this field i suggest some fonctionnalities, and if you have more please share it up 
* wen you create a propretie in archicad (dropdown list propretie for exp) you can see the propretie in bimx and also modify it by choosing another propretie from the drop down list, this can be helpfull to modify elements state onsite, for exemple, if you are on site, you can select the finished columns and give them "well finished" propretie, other columns mayhave some other states like "canceled", "bad execution" ,, you send this data ba k to archicad and the elements are updated, the schedule also update and we can know how much post we have to execute in future..
*connect bimx to mesure tools (laser meter), so we can take dimensions from existing site or room directly into bimx, this lines can be sent to archicad and start immediately your work (bosh offers such an app for it's devices, and this inspired me)
*surfaces , attributes can be modified on bimx, the app saves your choice and send it back to archicad,