In this Instructable, I will show you how to make your own app using Xcode on your Mac computer and then how to use the app to control an LED through an arduino.

Step 1: Materials

Arduino Uno Board

Arduino Ethernet Shield

LED

200 ohm Resistor

Hook up wires (if needed)

Bread board

iPhone with iOS 9 or later

Mac PC with Arduino Program and Xcode

USB Plugin

Rj-45 Cable (Ethernet Chord)

Step 2: Arduino Program

Follow this link to get to the arduino website to download the program if you do not already have it.

https://www.arduino.cc/en/Main/Software

Select the one for Mac OS X

Step 3: Arduino Code

Step 4: Xcode Coding

First Image is ViewController.m file

Second image is ViewController.h file

Third image is App Preview

Step 5: Testing and Simulation

First, run a test on one of the devices shown in image 1

If the simulation works, plug in your iPhone into your computer and select your device as shown in image 2.

Press the triangle or "play" button on the top right of your screen to run a test/simulation

(NOTE: During first simulation, it may take awhile for the simulation to load)

Step 6: Hooking Up the Arduino and Ethernet Shield

In the Arduino website, you will get an image like the one shown. You will plug in the USB chord into your computer and the other end into the arduino. The Rj-45 cable will plug in to your ethernet shield and wireless wifi router. Then, the first two buttons on the Arduino page like the image shown is what you need to press, "Verify and Upload" press Verify first, and once it is verified, press upload. You should get a message at the bottom of the page saying uploaded to board.

Step 7: Hooking Up Arduino and LED

Make sure the LED side that is closer to the resistor is the shorter (negative) side and the wire leading from the LED is plugged into the Digital Pin 2 and the wire from the resistor is plugged into the Digital Ground Pin (GND).

Step 8: Finish

Hook up the Arduino and Ethernet Shield like the image and make sure your app is on your phone, and your code for Arduino is uploaded to the board. Run your app, and flip the switch and the LED should turn on

Introduction: Control an LED With Your IPhone