The best alternatives to Truecaller are Hello, Callblock, and Bad Numbers. If these 3 options don't work for you, we've listed a few more alternatives below.
Callblock is the first app that lets you stop telemarketing phone calls in iOS (https://techcrunch.com/2016/09/07/callblocks-new-ios-app-will-block-calls-from-over-2-million-telemarketers/
Truecaller's iPhone app has been completely re-written from the ground up to be lighter, more efficient, but most important of all, 10 times better spam, scam and business call identification compared to previo...
RoboStopper is a cross-platform app that blocks all unwanted phone calls, with an optional bypass rate that spammers must pay. No foolhardy blacklists, and more flexibility than iOS’s Silence Unknown Callers so...