Two big takeaways here. One:
… in Android 2.2, the API to end applications was removed, closing the hole Advanced Task Manager was created to fill.
That’s right, task killers are no longer necessary in new builds of Android. I know this is ingrained into our Android psyches by now, but I have always been dubious of task killers, and this brings it home for me. Instead you should prefer (the unfortunately named) AutoKiller which will adjust the threshold at which the operating system should page/swap applications (root required, as is anything in Android). Remember, given the Intent/Activity model that Android pushes it’s always better to let the OS decide what should and should not be running.
Secondly: you can make some money in the Android market, only if the user does not have to actually discover your application. Advanced Task Manager has been in the “Top Applications” lists since Feb. 2009. Riding the wave, it managed to stay in the “Top Paid” lists well after the Market upgrade, showing up for me even on unrelated queries. To me this says the Market has potential, but is waiting on a revamp of the Market application to allow for any kind of application discovery to really bring it home.
Oh, and a way to purchase apps in more than thirteen countries.