I know this is a broad question (and a sensitive one) but would be interested to know some stats.
If using Google's AdMob service for your android app, can you provide an indication of realised advertising revenue. I can appreciate the sensitive nature talking about revenue but I have done Google Adwords for web based advertising and I haven't heard many successes. But indications would be helpful.
To give you more context, say you have a free game that gets about 10,000 downloads. What do is the expected average hit rate on adversting and then what sort of revenue has it generated.
Admob stats that might be a useful reference from my mobile app on Android.
The AdMob team may not be helpful but that's worth a shot. One decent way to eyeball this is to guestimate a range based on industry averages. Expect your eCPM to run anywhere from a couple bucks to about a dime. Then guess a range of impressions you'd expect to deliver a day. 10k users could result in 100k impressions a day but that might be optimistic.
100,000 / 1,000 * 2 = $200 /day
100,000 / 1,000 * .1 = $10 /day
Also, remember that just because your game has been downloaded 10k times doesn't mean all of those users will keep it. 80% retention rate is really good while 40% is not unheard of. To make the most of your app I'd advise you to take advantage of the house ads to promote your other apps. If they like one of your apps chances are good that they'll like others you've made and in a way it's an up/cross sell which is always easier than getting the initial download.
Some stooges say that you can't sell anything on Android and that free ad supported is the only way to go. Some stooges also make what many might consider spamy apps. I'm sure you're above that so consider offering both a feature or content restricted free and full paid versions. Also, consider in app purchases for micro-transactions or additional content as another revenue stream.
Welcome to making money on Android. Best of luck.
It would be very difficult to tell before deploying the App, the type of App do people just go in and out of the App quickly or do they use it for long periods?
The position of the Ads, there is a reason the Ads in Angry Birds obscure the game.
Having said all that, I have an App with 5000 installs 57% active and yesterday I made just over $2.
My sense is that you would get good info on this from the AdMob team at Google. It may be on an anonymized basis, but will be grouped by category and should give you much better data than a few random samples here.