The darker the shade, the better the service on Sensorly’s crowd-sourced service map.

With so many shiny new phones on the market this week, it wouldn’t be surprising if you’re thinking about switching mobile carriers for your next device.

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If so, the most important thing to know before making the switch is whether that mobile carrier adequately serves your area. Sensorly and OpenSignal are both services that offers an unbiased take on whether it does or not.

Just put in your ZIP code and cellphone carrier (or prospective carrier) and either site will feed you a map. The deeper the color in your area, the better the service. Alternatively there’s Dead Cell Zones, which highlights just the opposite.

Of course, like with any free service, there is a catch. Sensorly is crowdsourced, so it’s only as accurate as its range and number of users: “Since our data is 100% user-generated, the more people who join the Sensorly Crowd and use the app, the more precise it gets.” OpenSignal is the same way, collecting anonymous data from its app users to create its maps.

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So when your options are this or your mobile carrier’s take, Sensorly and OpenSignal are certainly less biased than the alternative. Crowdsourced mobile maps are just another tool to consider if you’re in the market for a new phone.

Screenshot via Sensorly