Finding Apps on my iPhone
You can launch an app on an iPhone multiple ways. A few of them are:

1. Swipe left (or right) until you are on the screen of the desired app. Then simply tap the image that is located above the name of the app and the application should launch.

2. Use spotlight search: To use spotlight search simply pull the screen down when you are on the home screen of your iPhone. Then simply type on the name of the desired app and it should appear. Then tap the image above the name of the app and it should launch

3. Siri: To use Siri to launch a app hold down on your phone's home button. Your phone should vibrate and then you should say: "Launch (the name of the desired app)". Then the app should launch.

These are a few of the basic ways to launch a app. There are other ways but they get more complicated.