I am looking to test a campaign with 2 or 3 traffic sources. I will be using Decisive but want to test against 1 or 2 others. I have heard inmobi and tapit come up quite a bit so I am looking into running the same campaign on these sources. When I look at Decisive's planner for the target country it shows about 47MM for Android. When I look at Tapit it only shows 6MM. For inmobi they don't have a planner but a rep told me they have "ample" volume in the target country.
Is 6MM too small a number where you wouldn't bother running a campaign with Tapit? Is there a threshold that is good to use when making this decision?
Thanks
If you can actually reach all of those 6 million people it's a perfectly fine number!
I'd test it, see what the volume was like, and work from there.
6 million? Do some math.
If your targeting lets you reach 25% of them that's 1,500,000 daily impressions.
At a modest CTR of 0.5% that's 7500 clicks.
If you have a 2.5% conversion rate, that's 188 conversions a day.
If the offer pays out $1, that's maybe $200 in revenue a day or $x,xxx weekly.
Good/bad? Who knows. Test, assess campaign performance and decide if you want to continue. Don't disregard lower volume sources - they may bring in high net profit and together can smash large sources - 20 small mobile sources might together bring twice the profit of 1 big source.
Given this is mobile, I'd even double the CTR assumption.
1% CTR given Zeno's other figures above means $350 a day or so.
I'd describe that as "not too shabby" 
Thanks!