Yet Another Call Blocker is described as 'A free and open source application that can block unwanted calls or warn about probable intentions of callers using a third-party crowdsourced phone number database (from some other proprietary app)' and is a unwanted call blocker in the security & privacy category. There are more than 10 alternatives to Yet Another Call Blocker for a variety of platforms, including Android, iPhone, F-Droid, Web-based and Android Wear apps. The best Yet Another Call Blocker alternative is SpamBlocker, which is both free and Open Source. Other great apps like Yet Another Call Blocker are Saracroche, Truecaller, Sereniphone and Silence: Block Unknown Callers.
i have been using truecaller but trust me it wasnt that good