Apart from something smaller to carry around, the tablet or smart phone has the advantage of a small screen. This may well improve the readability of presentations, as if the presenter can see the details on their small device it will likely be readable to the audience on the big screen. I attend many presentations which must have looked good on a desktop monitor, but have too much small detail for a large screen.
Something else I have found works well on the tablet computer is Skype with a headset plugged in for audio conferences. I use a surveillance style headset, which rests over one ear and has a lapel microphone. I have also installed the Adobe Connect App, but have not yet tried it with a conference. One concern is that there appears to be no way to change the video and audio settings to reduce data use (in Skype I set the video to low quality).
Berking, P., Archibald, T., Haag, J., & Birtwhistle, M. (2012, January). Mobile learning: Not just another delivery method. In The Interservice/Industry Training, Simulation & Education Conference (I/ITSEC) (Vol. 2012, No. 1). National Training Systems Association.