Is there an app that will block all calls on your smart phone, except for those numbers in your contacts list?

I think I’ve asked this before, but since there are news apps being developed all the time, I think it’s time for an update.

I get at least 2 or 3 crank or spam calls every day on my mobile phone. I’m looking for an app that will automatically block all calls except for those numbers that I’ve specifically entered for my contacts in the Contacts app.

I’m currently using YouMail. It does an OK job, but it doesn’t exactly work the way I’ve described above. It blocks some calls (based on other criteria), but many calls still get through.