With this method, you don’t need a third-party app. Call the person you want to chat with, then tap the “Add Call” button on your phone’s screen. Dial your own phone number—the one you’re calling from. This will take you to your voicemail. Once your voicemail has started recording, tap the “Merge Calls” button on your screen. Now, you’ll record your phone conversation onto a voicemail message. When you’re done with the call, you can tap the share button to export it to your Mac via Airdrop, to the Voice Memos app, or transfer it via email or text message. The file is recorded as an M4A, so depending on what you want to do with it, you may need to convert it to MP3 before uploading it to other apps.
In the Account tab, tap Voicemail settings Manage greeting. Tap the microphone. To save your greeting, tap Keep or Redo to record it again. Name your greeting and tap Save. View a tutorial on how to record a new voicemail greeting on your iPhone. Set a voicemail PIN. To access your voicemail by phone, you need to set a voicemail PIN. Open the

A downside to these apps—they are not as simple as hitting a key on the number pad, because you have to do the extra steps to make the merge happen with the third number doing the recording. However, they can all be activated in the middle of any phone call; afterwards you get easy access to recordings in the app and can play, download, share, or export them as desired.
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