Previously I mentioned a nice UITextField auto-completion library called HTAutoCompleteTextField.
Here’s an interesting open source component submitted Mazyod for autocompetion submitted by Mazyod that provides some very nice unique features called MJAutoComplete.
MJAutoComplete allows you to integrate with any text source such as a text field, text view or text storage. You can also customize the cells that appear with MJAutoComplete so you can do some neat thing slike include thumbnail images. A full demo is included demonstrating how to populate the auto complete list, and customize cells.
You can find MJAutoCOmplete on Github here.
An excellent auto-completion library.