So you have that awesome idea for an app that you think will be very successful and is not technically difficult to make (but a struggle to do yourself because you're not that good yet)
How would you go about finding a developer that's willing to hop on board, and how would you protect yourself from that developer just taking that idea for themselves?
This is a hypothetical question, but I'm wondering what are some thoughts on the subject.
Your best bet is probably to talk to a lawyer, preferably one that specializes in this sort of thing.
I expect they could help you come up with a set of contracts/agreements to be signed by anyone that you hire. (You'll probably end up with some sort of Non-Disclosure Agreement and employment contract with a Non-Compete clause)
The key for your particular question is the Non-Compete clause, which
... is a term used in contract law under which one party (usually an employee) agrees to not pursue a similar profession or trade in competition against another party (usually the employer)
An honest developer should be okay signing this sort of contract, as long as it is fair. (This sort of thing is pretty standard)
Nondisclosure agreements, employment contracts, and noncompete clauses protect you to at least some degree, although you should consult a lawyer for the specific case of your jurisdiction.
That said, you shouldn't be working with people you don't trust on at least some level. Would you hand a complete stranger your wallet and PINs?
When you hire someone, make sure they sign a non-disclosure agreement as part of the contract. While this legally protects you, in the end there's nothing that can prevent that individual from writing something similar ... or telling someone else how to do it.
If it's really easy to implement with just the idea, you don't have to worry about your employees stealing it. As soon as you launch, everyone else can steal it too. If it's a good idea, they will.
You can protect yourself a little with an NDA and a good employment contract, but mostly you should just look for people you think you can trust. If you worry too much about being stolen from, your idea will fail because you won't give your employees enough power and trust to do it right.
Just to put forth an alternative answer: if it's just an informal thing and you don't want to (or can't, for whatever reason) involve contracts and lawyers and so on, try getting some experience with the relevant language(s)/framework(s)/platform(s) on a more mundane project. Then maybe you will be able to do it yourself. (This also assumes that it's not something you need urgently)
"an app that you think will be very successful"
Most developers lack the "soft skills" necessary to make an application successful. If you hire a technically proficient developer most likely he/she will be delighted to leave the financing, sales, marketing, planning, etc to you while they hammer away at bringing your spec to life. In other words the success of you app depends very largely upon your ability to bring it effectively to market, NOT on your ability to protect yourself from your employees.
Let me tell you, it's never* the idea that makes something a success. It's the execution.
How many times did sites like Facebook pop up before Facebook blew up? How many people wanted to develop social networking sites, but failed, and we never heard of them? There's plenty we have heard of (Friendster, Live Journal, Orkut), and even then, they failed.
There are very, very few new ideas. Ideas are a dime a dozen. Sorry. Having an idea and making it a reality have nothing in common.
How many people are able to see those ideas to fruition? If your idea is good, you should share it with everyone possible. Get feedback and input, because you're never as smart, or in-tune to your market as you hope you are, or as others are.
If you're going to be successful, it's how you take your idea to market, not whom you share it with.
*Okay, okay, not very often.
You could enter into a Non-Disclosure Agreement (NDA) with the developer.
Don't hire someone, Partner with them. That way you're both in for the ride.
I would like to add that I came to the conclusion that its probably better/easier/cheaper (at least for some situations) to disguise the 'punchline'... make the description of the idea pretty generic, with enough specs to understand the scope of the project, but leave the 'special sause' for after you establish some sort of relationship/trust.