This article explains how to install the WeChat application on an iPhone or iPad by downloading it from the App Store.
Steps

Step 1. Open the App Store on your device
The icon looks like a white "A" in a blue circle. It is usually located on the Home screen or in a folder called "Utilities".

Step 2. Click on Search
The icon for this option looks like a magnifying glass and is located at the bottom of the screen.

Step 3. Type WeChat in the search bar
A list of relevant results will appear.

Step 4. Select WeChat
It should be the first result to appear under the search bar.

Step 5. Click on Get
The wording of this button will change, becoming "Install".

Step 6. Click on Install
If it's not your first time downloading WeChat, you'll see a cloud icon with a blue arrow instead of the button. Tap it to start the installation.

Step 7. Enter your security code or use Touch ID
If you are not prompted to perform these actions, skip to the next step. If not, follow the onscreen instructions to start the download.

Step 8. Open WeChat
If you are still on the WeChat page in the App Store, click "Open". If not, tap the WeChat icon, which features two white speech bubbles on a green background and is on the Home screen. At this point the application will be ready to be used.