We all know how helpful robocall blockers could be. However, they can also create their problems sometimes. Dan Hastings (a security researcher from NCC Group) has found out a few of the popular apps that are developed to block robocall have been transferring data to analytics firms without your permission.
Data harvesting is usually meant to make money on information, that has been a part of the whole problem. Many companies like the above ones earned profits by violating users' privacy while they were also defending their accounts from robocall intrusions.
Dan Hastings chastised the tech giant Apple by accusing it of not reviewing privacy policies, as well as not catching misuses such as Truecaller and Hiya.