I started developing in mid-April and released on July 1st. Most of the development was completed in about two weeks of evenings/weekend spare time; the rest of the time was spent tweaking and fiddling with graphics and sounds.
To motivate myself to complete it, I created the app record in iTunes Connect before I started working on the project. This gave me 90 days before Apple would take the name away. I plan on using this trick in the future when working on small apps.
Here are a few promo codes:
PJJLMMXX976L RKHAR9KXR3YM L7TY7LMXYJHF ANNH76FF7NPP 4TF63T9F49WR
Let me know what you think!