I just need to see the signal strength of WiFi stations I have around my house. It would be better to have it (signal strength) in a percentage format, because there some apps that show strength in some other difficult format.
If you are talking dBm, which you will see most wifi scanning apps use, it is actually not that difficult to understand. Basically higher numbers are better, and even negative numbers actually represent positive quantities, just smaller ones.
Zero dBm equals one milliwatt. A 3 dB increase represents roughly doubling the power, which means that 3 dBm equals roughly 2 mW. For a 3 dB decrease, the power is reduced by about one half, making −3 dBm equal to about 0.5 milliwatt.
There is also a pretty dang useful chart.
Sorry for not answering the original question, but I think with this knowledge you will be able to powerfully determine the strongest source of transmissions.