Have you had a chance to look at truecaller? It crowdsources data on who is spamming, advertising and marketing. In India where you get sales pitches even from

Have you had a chance to look at truecaller? It crowdsources data on who is spamming, advertising and marketing. In India where you get sales pitches even from a personal number, truecaller is a savior. Instead of having to answer questions, crowdsourcing would be a viable one