What had to be a nice day:

So last week a friend asked me if I wanted to come.
Some days (2) later I said ok and asked him what time.
I’m also doing a project with him (he isn’t a dev), so I thought I add new features and show him the ideas.
Yesterday he wrote a message: “My family is coming, Sorry, I need to cancel”
I’m so angry. I worked long on these features to make him happy, and show ideas. And then when nearly everything is done he cancels.
I don’t know what so tell him/do. What would you do?

Surely you're doing the project for more than just him?

@milkybarkid no not sure...

You need to choose your friends/business partners carefully. I give people the benefit of doubt unless I have solid evidence to the contrary. He didn't ask you to code the features and he claims his family came at the last minute so he hasn't done anything wrong. It's good you're excited about your new code but realise, cancelled meetings and people pulling out is part and parcel of the software industry. You'll end up with high blood pressure if you get annoyed every time it happens. Just reschedule and move on to other projects / gaming / life etc.