Having released my first app at the end of October, I can confirm building the app is at the highest "only 50%". Having had very little interest for it. (less than 10 buys) I now fully understand marketing has a much larger role than a developer like me would have liked. 2012, I will learn iOS, yet I will also learn marketing. My first app was created with Titanium too, yet I feel it is important to learn iOS.
Just a thought - the screenshots look really great, but you will definitely want to write a much longer app description. I would NEVER buy the app based on that description alone since it is $3 and I don't even fully understand what it's for. Why would I want to be reminded of certain words? Is it like a flashcard app?