I spent a couple of hours trying to fix my WiFi network based on low speed readings from the FCC speed test app (which had worked fine previously). It was indicating less than 1 Mbps for repeated tests on two different days. I finally downoaded two other speed test apps which both show 10 Mbps using the same server location. Doing some other download tests confirmed the 10 Mbps readings.
I checked the reviews for this app on the iTunes store and one other user reported the same problem.