Question
I don't have much cash to work with and I am working on developing a mobile app. However, I want to find a good designer to work with. I don't want to give them equity but I do want to pay people for their work. Would you recommend promising (in writing) a profit percentage? If so, how much would this be?
Answer
If you can find a developer who would accept your proposal, it is a good deal for you. Most developers worth their salt will not agree to something like it unless you have some unfair advantage.
If a developer is free they can develop on their own ideas and keep 100% of the profits and equity. However, you might be able to find new developers or students who are looking for experience with a model like this.