This is a single view app that allows you to connect to an Arduino Bluno board via bluetooth and control each LED individually by either dragging across or tapping the blue dots.
Build and demo video on youtube Complete build instructions posted on Instructables.com
0.0.1 This is the very first version of this app and it's only been optimized for the Iphone 6. If you feel comfortable loading the project into Xcode, it shouldn't be too hard to modify it in any way you like.
In the arduino folder you'll find the logic for controlling the led pixels. Push that code to your board via Arduino Sketch and you should be good to go.
Also included is the Adafruit library that has all sorts of cool effects like the rainbow mode.
This app is based on the Arduino Tutorial posted by Owen L Brown here.
If you want to start making your own bluetooth app for IOS I would suggest reading Owens tutorial.