Control an igniter remotely from your mobile phone
Here is a wireless igniter controlled by a mobile phone. It can be used to ignite fireworks or for model rocketry from a safe distance. The main components are: an android device, bluetooth module, arduino board, ULN 2004, relay and a short lenght of nichrome wire. The entire circuit is extremely easy to replicate.

The device works as follows:
1. The phone and the app I wrote for it sends a byte through bluetooth connection when you press the fire button
2. The byte is received by a bluetooth module inside the ignitor. The module sends it through serial to RX pin on the arduino board
3. The arduino board and a sketch I created checks if it received the right byte and if it's OK it sets pin 7 to HIGH state
4. A ULN2004 switches a relay on
5. Current heats up nichrome wire wrapped around a match and ignites it

If you like to learn more about interfacing microcontrollers and android devices consider viewing this -> https://www.instructables.com/id/How-control-arduino-board-using-an-android-phone-a/you how to create a remote

Step 1: Electric Igniter

The most basic electric igniter is a length of wire. Most thin wire will do, but nichrome wire, which can be found in old hair-driers and similar appliances, is the best. Cut 1.5 - 2" of wire and wrap it around a match - make sure there are leads to which you can attach aligator clips. It's good idea to use superglue to secure the wire in place

Step 2: Wiring

Here is wiring. The hardest to get part is a bluetooth module. I used a BTM222 chip on a breakout board which is populated bu a voltage regulator and a level shifter (Don't ask me where I got it - I bought it from a local guy who makes them - don't know how to contract him). Any bluetooth module that support SPP and master mode will do.
The rest is pretty self explanatory.

Step 3: Arduino Code

cope and paste code:

const int ignpin = 7;      // the pin that the LED is attached to
int serialA;
void setup()
{
// initialize the serial communication:
Serial.begin(19200);
// initialize the ledPin as an output:
pinMode(ignpin, OUTPUT);
}

void loop() {

if (Serial.available() > 0) {serialA = Serial.read();Serial.println(serialA);}

      switch (serialA) {
      case 49:digitalWrite(ignpin, HIGH);
      delay(5000);
      digitalWrite(ignpin, LOW);
      serialA = 0;
      default:

      break;
}

}

Step 4: App

I created the app using MIT's app inventor.
Here you can download the app -> https://docs.google.com/file/d/0B_PfPoEotOF8ZzJrOFF2NFZiUGM/edit?usp=sharing

and here is source code you can download to modify the app -> https://drive.google.com/folderview?id=0B_PfPoEotOF8N2JwT3RSX011SjQ&usp=sharing