Ah that could be the case... now that I'm thinking about it, this has always happened inside. Last time it happened I was in a Walgreens. It has happened at work too.
I work in an xray department in a hospital but the hospital uses Verizon services so they installed stuff that strengthen the signal but only 3G, gives full service even inside lead lined walls. Never could get 4G here but now I'm starting to see it strongly when I go outside or upstairs and occasionally very weak inside the department, so I think that's the problem. It wants to switch to 1 or 2 bars of 4G in the department instead of just hanging onto the solid 3G signal. I could just set it to CDMA only at work to avoid the switches that I believe cause the dropouts of data but it happens very rarely and doesn't swam to effect battery to much.
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