Ok, since I've been doing nothing but helping financial companies market their software and services online for over 20 years, this is pretty much my area of expertise.
The biggest issue you are going to have with your entire project is going to be marketing it. In my past experience, most guys who build specialized apps like yours put almost every penny into the development of the product and then have virtually no money to market it. So eventually the project folds because there's no marketing plan to reach new customers.
Maybe on a bare cost level, but you're not taking into consideration how much money you'll need to spend to acquire a customer. Have you thought about how you're going to find the dedicated options traders who would even be interested in such an app? Since there's going to be turnover in your subscription business, you'll need to seriously think about how you're going to constantly attract new customers to make up for the ones that have canceled.
Furthermore, a $9.99 price point is way too low. That price point is assuming a very big potential market size, but in reality the market for that product is extremely small. And the primary reason is because your product is elective, and not essential.
