THink about how far apart the Wi-Fi hot spot is on a Smart phone or on a Jet-Pack.. You will have no problems with both devices on the same mast UNLESS... ....
The best antennas for both greatest Wi-Fi range and Greatest Cellular range are, of course, DIRECTIONAL antennas.
Aiming can be an issue if the Wi-Fi router is say East of you (As the one is where I'm at) and the cell tower, SOUTH,
One soution to this is a mast within a mast.. put the smaller antenna on the top mast, run the coax up the center, the smaller mast is longer,
The larger mast carries the longer antenna, the coax runs over the mast on that one.
Also, a side mounted antenna will tend to be directional (if you put an omnidirectional atop the mast the side mounted antenna may exhibit direcitonal tendencies.
