For the month of April I was consistently making around $20/day in combined ad and sales revenue. As I've mentioned, the way I'm serving up ads in my apps, as dialogs between hands, has apparently habituated people to ignore the ads more and click through less. I've slid down to around $10/day for the past 10 days or so. I'm serving up between 200,000 and 250,000 ads per day, but seeing smaller and smaller click-through rates. The lowest daily rate per thousand ads so far has been $0.02. I haven't seen a 1 cent day, though I'm morbidly curious to know if it can go to fractions of a cent.
In the meantime, I'm trying to be a bit more patient about the release of new apps. I'm holding Golf Solitaire and trying to test it a bit more, hoping to release a more polished product with fewer bugs. I broke my neck trying to get Spades out to be first to market, and that was probably a good idea, but I don't think there's a dire rush on this app. Plus, I'm going to try to release it either Sunday night or early Monday morning. I don't have hard data, but it looks to me as if those are the days when the fewest apps are released (which means the apps will stay in the New Content section longer), while usage is still quite high.
One interesting trend I notice in my ad stats is the number of ads served by day of the week. I serve many more ads on Mondays and Tuesdays, while the number steadily declines throughout the week. It's lowest on weekends, which seems to indicate that people are playing card games on their phones either when they're at work or home, and are probably filling up their leisure time on the weekends with other stuff. So I'm going to try launching my new game on Monday, assuming that all those bored people at work are looking for something new to play. We'll see if it makes a difference.
In terms of tracking usage, I came across Flurry, and analytics package for mobile apps. I downloaded it, but haven't put it in any of my apps yet. Those with ads give me some idea of usage patterns, though it would be nice to have more detailed information. I won't by trying it with my new game, though.