Wifi Analyzer will provide useful information about wireless signals around you. App supports 2.4Ghz and 5Ghz.

- Helps to find optimal placement for wifi receivers
- Wifi Analyzer provides you information individualy on wifi channels
- Shows signal strength in history graph
- Wifi Analyzer recommends the best channel for new AP
- Information of the channel width (20/40/80MHz - only Android 6+)
- Wifi Heat Map - let you create heat map of wifi signal quality around you

Version of Wifi Analyzer without ads is available at: https://play.google.com/store/apps/details?id=info.wifianalyzer.pro

Note: Android 6+ (Marshmallow) requires LOCATION permission and location enabled - the reasons explained on the official website android.com: http://developer.android.com/about/versions/marshmallow/android-6.0-changes.html#behavior-hardware-id

Alternative for Android 6+ possibly without need of LOCATION:
https://play.google.com/store/apps/details?id=info.wifianalyzer.sdk22
(Wifi Analyzer app made on older SDK could work in compatibility mode)