Free Advanced Task Manager was released in November 2009. Revenues are from AdMob.

2009
November: $109
December: $231

2010
January: $1000
February: $2900
March: $2700
April: $3000
May: $4100
June: $5000
July: $6200
August (not complete): $3400
SUM: ~ $29,000

A few points I want to make:
1) Android is a viable revenue stream.  Although $80,000 total isn’t a lot compared to some of the overnight millionaire stories you hear about on the iPhone App Store (not sure if this is before or after Apple’s cut), you are able to generate good returns. On average, I’m getting around $10,000 a month after all cuts.  Along with my full time job at IBM, I can say I am doing relatively well.
I also sold this as a 99c application.  I am sure if I had pushed up the cost, I could have generated a lot more.  Additionally a number of clone apps appeared that replicated my feature set and were major competitors to my application.

2) One might argue that my app did appear in the “Top Paid” and garnered more exposure than others.  This is true but the Top Paid list changes often.  The algorithm used by Google to rank applications on this list includes downloads, ratings, uninstall rates, etc.  So new applications can jump in easily and replace older ones.  There are a number of other applications that probably generate significant revenue but are not listed here.  This is also a reason why widgets fill up this list.

3) Revenue picked up significantly when the Droid on Verizon was released and after Android 1.6 when the Market app changed to highlight paid applications.  There are definitely certain trends that went along with other phone releases as well.  I may have had a head start, but did not gain significant enough revenue till the end of 2009.

4) Google Checkout and the Market app are probably the biggest things holding revenues back in Android right now.  The market application glitches often and causes download problems all the time.  I’ve lost count of all emails I’ve gotten over these past two years from users asking why my application won’t download.  I’ve gotten so sick of these that I ignore most of them–I don’t even bother pasting a canned response.

The market app needs to highlight other lists such as “Top Grossed,” “Most Downloaded,” “Highest Install Rate / Top New Apps” as a way for users to find applications.  Discovering applications is a problem right now.  With these additional lists, users can click through them to find other high quality apps - unlike the “Top Paid” list right now which is very arbitrary and is not an indication of the true top applications in Android.

Google Checkout is also a big problem since it doesn’t accept payments in a number of countries causing Android to only support around 13 countries compared to 90 on the iPhone.  This is inexcusable.  The reporting feature on Google Checkout is also horrible.  It was quite painful to generate tax reports.

With that said, Google is doing a number of things to improve the situation.  Paypal as a payment option will be extremely helpful.  A website to browse Android applications and to send it to phones for installation will most likely raise applications discoverability and revenue significantly.  Additionally with the growing rate of Android adoption, I only see revenue going up and not down moving forward.

5) Admob is a viable revenue stream.  At one point, it generated more revenue for me than my paid application.  My free version was never in the highlighted list but it still accumulated a lot of users.  I have around 700,000 downloads, daily requests of 300,000, and daily clicks of 3500.  Most of the clicks came in from North America, Europe, and Asia.  Translation will probably help in those locations.

6) And if you are wondering, I have around 90,000 total installs and an active rate of around 65% for my paid application.

7) 24-hour return rate - I have read multiple stories that the 24 hour return rate hurts sales.  In a way, it does but it’s not bad.  On average I get a 5% return rate a day.  However, I would rather have the ability for users to test applications and then decide whether to keep them or not.  One of the reasons why iPhone apps may generate more is because of users buying stupid apps and having no way to refund them.  This is a reason why fart apps do so well on iOS and not on Android.  Most of them will be refunded.  Apple does not dare to implement such a feature for the iPhone knowing for sure this will hurt app sales.  They try to protect revenue stream for developers and not for users.  As a developer, you won’t care, but it’s bad business to always try to trick users into buying apps.

8 ) Piracy is a bigger problem but google has corrected this.  The licensing model should keep pirated apps to a minimum.

Conclusion:
I wrote this to highlight how Android is a viable revenue stream after reading countless stories that it is not. Things will improve moving forward and will be a good competitor to iOS.

Currently, I’m working on a significant update to my application to add new features to it so that users will still find it useful.  Look forward to an update that will provide the following:
1) Backup capabilities for saving and restoring applications, sms, and other android-related items
2) Applications management for easy ways to install, backkup, and uninstall applications
3) System information on how to squeeze the best performance out of the phone
4) Direct links to Android’s Services and force-stop UIs
5) More to come..