“An app that converts your daily change into bail money to free black people.” That’s what Kortney Ryan Ziegler, a social engineer with a PhD in African-American studies, tweeted in July. https://twitter.com/fakerapper/status/889197985678073856The response was instantaneous—and overwhelming. Nearly 200 people replied with offers to help. That was the start of Appolition, which converts users’ spare change into bail money.

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