New Yorkers on Mobile Messaging and Implications for Privacy (2015) [pdf]

A couple of quotes:

"Just as economics can drive people into unsafe living conditions with people they don’t trust, the cost of cellular service drives people into family plans with people with whom they have an adversarial relationship. Saving money with a group plan is a powerful incentive. Combined with inertia and an aggressive customer retention industry, our participants were in legacy family plans that no longer reflected their family or living situation. People remained trapped in plans with estranged partners, distant family members, and others they didn’t know well, such as temporary roommates, or people they’d lost touch with."

[...]

"The participants had strongly adversarial relationships with the cell phone providers, like Cricket or Metro PCS, that they saw as a threat to the reliability of their phones. In particular, they believed the carriers were trying to push software updates to their phones to break them, which would in turn would force them to upgrade. This would represent a financial benefit the carrier, at the expense of the participant’s job, safety, and well­being."