One of the new features in iOS 10 is the CallKit Directory extension that lets 3rd party apps to provide caller ID and spam detection in the native iOS dialer. Using these apps, you get spam id on the incoming call screen and also in the call logs in the Phone app. Apple has just started to approve these apps and first few are online right now.
If you are in US/Canada/UK, try the Hiya app (https://itunes.apple.com/us/app/hiya-caller-id-and-block/id986999874). This used to be called Whitepages ID before. Their Android app was one of the first apps ever on Android and their service ships as default on all Samsung Galaxy devices.
If you are in Korea, try Whoscall (https://itunes.apple.com/us/app/whoscall-caller-id-block/id929968679). Their US database is lacking but they have best data for the Korea market.
If you are in India, the best option is Truecaller. Their iOS 10 is not live yet but expected to launch shortly.
If you are in US/Canada/UK, try the Hiya app (https://itunes.apple.com/us/app/hiya-caller-id-and-block/id986999874). This used to be called Whitepages ID before. Their Android app was one of the first apps ever on Android and their service ships as default on all Samsung Galaxy devices.
If you are in Korea, try Whoscall (https://itunes.apple.com/us/app/whoscall-caller-id-block/id929968679). Their US database is lacking but they have best data for the Korea market.
If you are in India, the best option is Truecaller. Their iOS 10 is not live yet but expected to launch shortly.