Can I get sued for the following reasons?

I recently was abroad and met up with a cousin of mine. I chilled with him and he said he had this mobile application idea that sounded very good to me. I told him I could make it and then I expanded his idea with some of my ideas to make a very good idea that I think has a chance of becoming popular. However, in the beginning of developing the app, he invited two of his friends for no reason to our conversation of app development. They have nothing to contribute to this project. In fact, I've spent 100+ hours on this app just to build the databases and learn how to code in multiple programming languages that were needed to get this app done in the android os and iphone os. Now I don't wan't to cut off my cousin or anything, but I feel entitled to much more than 50% due to the fact that most of the ideas of the app are now from my original ideas, and I did all the work on this app. The thing is I had a conversation with them on facebook of me being very optimistic with working with them. However, none of them have contributed anything to the project. All they did was give me an inspiration idea that they never would have pursued and I did everything. I don't know what to do. I definitely am not giving them my code for an equal share. I didn't sign anything and this is MY code. What are my legal risks?

Added (1). They have not provided any funds.

There's no written contract.

And they have not helped work on it at all. And when I mean at all, they probably don't even now how to print the string hello world in any programming language. They don't have anything to offer when it comes to helping besides marketing where they are from. And marketing is not worth a fair share of equity since I created the entire project.

Added (2). They have not provided any funds.

There's no written contract.

And they have not helped work on it at all. And when I mean at all, they probably don't even now how to print the string hello world in any programming language. They don't have anything to offer when it comes to helping besides marketing where they are from. And marketing is not worth a fair share of equity since I created the entire project.

Added (3). *know

Short answer yes… If they can prove they were part of the partnership to develop this.

However if can prove they didn't provide funds, never had a legal binding document, and did no work or if they did and that it was negligible to deserve only a small percentage then you'd be safe. At this point either speak up and say look you are going your own way or they have to help.

Just a note to remember the facebook founders were sued since they took someone else idea, or at least in the view of the court they did.

Delete this post, talk to a lawyer don't admit anything in writing, online, anything that can be used in court, don't facebook about it, tweet, text, nothing