Why we like it: OpenSignal collects stats on cell and wifi networks around the world through it’s Android App. Users of the Android app pass anonymous reports to OpenSignal on the signal strength that they detect. That data is then compiled into heatmaps which are overlayed on top of a Google Map using an ImageMapType.
Users can also see their local cell tower or wifi routers.
This is a innovative use of Google Maps to show useful information to the user.
Posted by Mano Marks, Maps Developer Relations Team 
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