inSSIDer - inSSIDer Essential makes it easy to maintain small business WiFi.
eero - Blanket your home in fast, reliable WiFi
NetSpot - NetSpot is a free app for wireless site surveys, Wi-Fi analysis, and troubleshooting
Plume - App for writing documents, scripts, books and more.
Homedale - With Homedale you can search for Wi-Fi / WLAN Access Points and monitor their signal strength.
MIWIFI by Xiaomi - Wifi router beta with a twist: you build it yourself