Build for money. It is not as bad as it sounds.
I keep hearing things like "don't build for money" "don't follow money, follow a passion. Money follows." and many others that collectively make building for the dollars $$ seem bad.
Money can be one of the biggest motivators, SO big that makes you jump out of bed in the morning to your work table. Remember the day you saw your first ever sale notification? How motivated were you the day after?
"Don't follow the money." is simply a guideline, not a hard set rule. Successful individuals and businesses have several times opened up they did it for money, you can too. Nothing wrong with that.
It does not really matter why you do it for, what matters is the outcome. Some are motivated by Daddy issues -he went out to buy milk and never came back, so you create the "Where's my Dad?" app to find him- and that's fine too.
Loving money does not guarantee that money will love you back! Success is like a computer, it takes input and gives you output. The reasons for submitting your input don't matter, really; who cares?
What matters is to find the input that will produce the desired output. Simple.