Okay so I am working out how to zap. Not built in on Damus. Looks like isn't within Apple store rules.

So there is a work around. You can add the zap lightening icon by going to https://www.zechendorf.com/2024/01/05/enabling-zaps-in-damus.html on your iphone and click on enable zaps.

Can only zap one amount though (1000 satoshis).

Thanks @suhail

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