What app allows me to block "probable" spam calls I receive 2 or 3 calls per day from random spammers. I have tried blocking the numbers, but it is no use as they just call with new numbers. Is there anyway to avoid this? I suppose the end solution could be changing my number with a new sim card.

I have tried the app MrNumber, and I have tried a few other apps, but they all suffer from the problem of only blocking single numbers. Spam callers have too many number to utilize. Are there any apps that come with an extensive black list pre-installed? Or some method of detecting what other people have marked as spam?
Try True caller, it comes up with the preloaded blacklist and spammer numbers and keeps on updating..it has some interersting features too..