Wifi Analyzer might be a bit more popular than Acrylic WiFi Heatmaps. We know about 1 link to it since March 2021 and only 1 link to Acrylic WiFi Heatmaps. We are tracking product recommendations and mentions on various public social media platforms and blogs. They can help you identify which product is more popular and what people think of it.
Take a look at Acrylic (acrylicwifi.com). Last I looked, licensing wasn't onerous. Source: over 2 years ago
I've not looked in to new apps in years, I still have access to the old free version of inSSIDer but I've also used Wifi Analyzer from farproc (Android only I believe). Cannot vouch for the quality or safety of either at this point. Source: almost 3 years ago
NetSpot - NetSpot is a free app for wireless site surveys, Wi-Fi analysis, and troubleshooting
inSSIDer - inSSIDer Essential makes it easy to maintain small business WiFi.
Ekahau HeatMapper - The Free Wi-Fi Coverage Mapping Site Survey Tool
TamoGraph Site Survey - Wi-Fi site coverage survey and modelling application
Vistumbler - Vistumbler is a wireless network scanner for Windows Vista and Windows 7. Features:
Acrylic Wifi - Acrylic WiFi is a free to use WiFi scanning and channel scanning tool for the Windows operating devices only.