Just tried out the first few levels. Fun little game. The add ons for hints is an easy standard way to monetize a free game. I can't offer much advice graphics,

Just tried out the first few levels. Fun little game. The add ons for hints is an easy standard way to monetize a free game. I can't offer much advice graphics, but you might want to look at making the marbles look like marbles. Polish up the visuals just a bit. Feels like it's 95% of the way there. Other ideas: Look into some way to compete with other people. Some way to share it. Add the ability to text a link to the App Store to a friend. Only ask for the contacts permission when someone initiates that feature. Just keep iterating on the game and polishing it. You guys will get more ideas as time goes by. Expect the popularity to fall off at some point. That's normal. Apple looks for apps that really show off the platform. Being in the top 30 is great. If the visuals and sounds were a little more polished there's a better chance your game might be featured. This can be really great for boosting you higher, though it's not a permanent bump. Apps have life cycles. Do the best you can now and learn from it. Invaluable lessons for doing more apps in the future.