You can do it. Even if you wanted to do broadway, you could do
it, although you might have to down some anti-anxiety pills or
eat a banana (old stage fright trick that actually works),
before you went in.
The app route is definitely safer as the competition won't be
staring at you, raising eyebrows and such. What's the worst you
get? Spam? Not as many stars as you like? You're absolutely
right that the million dollar app is the less risky venture.
The only times you'd incur costs is whatever it takes to get it
on iTunes, and then any marketing that you -choose- to pay for.
But marketing can be completely free, especially if you get
word-of-mouth and have an entusiastic following.
