I have terrible reception indoors (in a "high signal" area) and a $30 Sprint SERO plan. Called 877-775-4886 (thanks, goodman @ SlippyBargains) . I deliberately called from the worst corner of the house and the call was dropped twice but the rep called me back (!). Airave for free. Initially wanted to charge $5/month, but then I asked him if it was true that this would enable other Sprint customers to call out through my Internet connection, and didn't it sound then as if Sprint should be paying me? He "verified with his manager" and the charge was dropped.
This adds a new line to your account, so although you will may not pay Sprint, your bill will increase because of "regulatory fees" that depend on your State and city.
You know, you could make a very workable Faraday Cage from some aluminium foil that should replicate the typical Iphone antenna reception...
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