I know many find S-Corp to be a better option (more straightforward with taxes/etc).
However cost-wise, both are about the same to start and file.
I don't know that either option is more official.
Depending on which state you are in, the taxes may look diff depending on what you do. CA for example has a $800 tax for corporations and LLC's, so being a sole proprietor is better/cheaper.
As to the apps, is it 100% of your income/time? if so, then yes, absolutely form it.
If not, then wait until it is a meaningful amount before you start dealing with complications on the tax and reporting side.
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