I am a software developer at a small company, 4 people in total. When I started to work there, one and a half year ago approximately, I entered as a intern, with intern duties and an intern pay, as the time passed, I started to grow within the company, my duties and responsibilities started to grow as well, but the amount that I earn is almost the same, except for a raise that I got some months ago. I made numerous projects for the company, started to learn Android programming from scratch and made a number of apps, of those, one is an app we offer to our clients that already have our desktop solution and ask for a considerable amount for it, the payment is monthly and when I made that app I was promised 50% of that money, the app is up and running in more than 40 devices and guess what: never saw a penny of it. Within one year, my internship contract expired and I didn't made a new one, so, I don't have any bonds to the company whatsoever. The big advantage of working there is that I don't have fixed hours, as my college's classes are all in the morning, I work only on the afternoon for 5 or 4 hours a day and still make the same amount. I can take pretty much any day off as long as I have a good reason to do so or leave early if needed (I've worked in other places before with fixed hours, and I know this isn't an easy task).
So, the big question is: should I demand/ask for a formal contract or something like that (and maybe a raise, since I am still making almost the same as when I started as a intern) and for the compensation I was promised for making the app in the first place? My boss is a real nice guy, I feel extremely free to do anything in the office, new projects I come up with, discussing ideas, telling jokes, is a real nice place to work, I don't want to risk losing any perks for pushing things too far.
*Edit: I don't know if the background (country) is really important, but for the record: I'm uneasy about the formal arrangement and contracts of work because I know my boss is against bureaucracy and my country is world famous for it's bureaucracy, I'm in a comfortable position at the moment, I fear that demanding a formal arrangement from him could put me in a bad position, something along the lines that I'm not as comfortable with his word as I was before.