I have to admit that HK Junkcalls is absolutely a product by accident. So far it has been downloaded over 100,000 times for the past 10 months.
The application does its work by importing numbers marked as junk call to your iPhone address book. Initially, the program only needs to import 2000 numbers. However, the list is slowly growing all the way to 8000 numbers and counting.
The addressbook in your iPhone is actually powered by an sqlite database. The bigger the list, the slower the your iPhone can properly lookup a phone number, which affects the performance of receiving a phone call. Above all, syncing the huge list of address book with your Mac is definitely not something very funny.
The good news is, iOS 4.2 and above let you put address book numbers "on your iPhone" only (first tipped off by a kind poster at mac.hk).
Therefore, I will restart developing the HK Junkcalls iPhone app more actively.
