First it is not the Wi-FI you want to boost it is the CELL signal
There are several options.
First... Within limits (In this case the range of the Wi-Fi Hotspot) HEIGHT IS MIGHT.. so if you were to put the JetPack atop say a 25 foot flagpole. it will see farther Or even up on the roof.
Second. you can use a better antenna, or you could, in theory, mount it at the focal point of a parabolic reflector of the proper size (Even a common 18" (or larger) round Sat dish will work nicely) and again as high as possible. This means you need to aim it however.. The bigger the dish, the higher the gain and the sharper the aim.
There are other ways to do it as well and you can use something like a Wilson amplifier as well. Wilson makes some decent antennas and MFJ (Specialises in Ham Radio gear) I believe makes a yagi for Wi-Fi use. Very high gain antenna.