Hi, on the Signal GH App, use the second page view for all the details of strength and Quality. see screen shot:
.
Also, I noticed on your TV Fool link, that NBC, ABC, CBS (and even PBS) are closer ( between 15 & 20 miles) and in the same general direction (NNW) where FOX is 33 miles away and is NNE. CW and MyTV are very close, around 8 miles, but like FOX they are in the North direction at 4 degrees.
So, you do have a challenge with FOX at 29 Degrees then around to ABC at 291 degrees. That is 98 Degrees total and most directional antennas suggest they are good for around 90 degress. But, i agree you should try a directional. Get it from Amazon, send it back if its not better. I use a RCA yogi style directional antenna. Its outside on the corner of the roof above the gutter. It says it is a 60 mile reach, I am only 10 miles away so can't say i need it, but I am getting 90 - 100% on most stations.
One other idea for you is on your cable connections. A splitter will steal a ton of signal from you. As a test, try connecting the cable from the antenna to one of you HDHR's without any splits and see if you pick up more signal in the Signal GH app. I had a 6 way splitter I was using but did not need, cut back to a 2 way and my CW became a watchable channel.