Step 1. Head to the Messages app on your iPhone.
Step 2. Tap on the iMessage conversation. If you want to add a new contact, tap on the compose button in the upper right.
Step 3. After that, you need to tap and hold on to the gray audio wave icon. It is available in the typing box on the right side.
Step 4. Now, you can simply speak your message while holding on to the microphone.
Step 5. After you complete your message, you can release the hold.
Step 6. To send a voice message from your iPhone, just tap on the bubble icon with an upward arrow.
Step 7. In addition, before you send your voice message you can hear it by tapping on the triangle button. If you want to cancel it, tap on the Cross button.
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