What type of issues are you having. Besides the obvious one. Over the years it has become a little harder to configure. Program or make changes in terminal. I know CIs, datamate ucis and wincis are all helpfull. Front end is always the best. My customers are pre 3.6. Most of the time. Know what the best would work for you is hardware.
I am not sure I understand how I can see the VAV's with a smart device. Are you talking about a smart phone with some special software? I know Johnson Controls has bluetooth devices,not aware of Siemens having the same. I had the Siemens service tech come out and he recommended getting the above software and related cable. If an easier way is available I am all ears. I would also like to change CFM setpoints on the ATEC as well.