1. Propose what voice messages should look like visually. Look at the examples from WeChat, Whatsapp, Telegram, FB Messenger
3. Come up with a proposal for Drafty to encapsulate the voice data. It should be very similar to images an attachments: small files should be sent inline, large files uploaded to the cloud.
4. Talk to me, make sure I agree with your proposal.
5. Select the client you want to work with first: webapp, Android or iOS. Make sure you understand how the client implements Drafty.
6. Implement and test the proposal.
7. Send me a pull request.