Hi HN -- I'm the blog post author and one of the people who built this, am happy to answer any questions about the hardware/software behind it!

Any plans on making one that can move around on wheels?

Haven't thought about it much -- my first thought would be that the solution in the blog post could be the right one for a small office where movement of the base isn't necessary, and for one on wheels you should just go buy from Double Robotics. Their product looks really nice.

If I had to build one that moves around, I'd start with investigating the Roomba API, with an aim to mount the iPad on a Roomba and expose remote control of the Roomba to the chatter. You wouldn't get as high off the ground as a Double robot without making the mount unstable, though!

Any reason you went with the Bescor over just a servo motor?

Probably just inexperience! Do you have any particular parts in mind?

You could have rigged up something like this: https://www.servocity.com/html/s3102_micro_mg.html#.Uyu11fna... to the PWM output of your Arduino.

This would have moved the iPad around, the same way as the pan tilt head.