Good for you! That is like 6MM a year! Pretty soon you can retire!

Do you get most of your revenue from Ads, paid apps or In App Purchase?

Yeah, I wish it were 6MM a year. Anyways, I get about 40% from In App purchases and 60 percent from ads.

Your math is off by an order of magnitude, but 50k a month is still amazing.

Oops...LOL ... I got too excited!

Which applications if you don't mind me asking?

Sorry, I don't want to give away my identity.

Wow, would love to know what are the apps too. Or perhaps, in what category / categories are your apps in?

Entertainment, lifestyle, and games.

Cool, and do you have any advice for iOS developers to achieve the similar kind of success that you're having?

If you are just starting, I would suggest creating a few apps and seeing which ones catch on and then focusing your efforts on those. Create apps quickly to test an idea, and then iterate quickly when improving an app. As for the type of apps, I believe ones that have decent growth and retention are best. I don't like apps that just focus on growth, because it is not too sustainable long term.

You sir, have made some pretty good points there. I'm just starting off, looking to launch my app in February. These shall help me in the long run.

What have you found to be most effective for marketing your apps?

I've tried multiple forms of marketing. 1. Admob - Got users to the app, but the app did not retain those users and it was quite expensive to even get them to the app. Over $1 per user for me. 2. Tried facebook ads. Just a complete failure for me. 3. I cross promote my apps within my own apps. That does ok. I'm not exactly sure the exact amount of traffic it drives, but it probably accounts for 5% of the user base on the apps i promote. 4. Facebook, Twitter Sharing. This probably accounts for 5 - 10% of new downloads within an app.