appMobi pricing is geared towards indie developers. We really don't want you to lose money from trying to create an awesome game.
If you don't use any cloud services, everything is completely free (cloud services: push messaging, playMobi, Live Updates, Analytics, IAP ).
If you do use our cloud services and use In App Purchases or appMobi Ads, then you aren't charged for the first 10,000 MAU's and when you hit 10,001 you owe .10 per MAU a month.
No Lose guarantee: Let's say you owe $500 to appMobi but only earned $400 in that timeline. We only charge you half of your earnings, so you would only be charged $200.
The third option is for Enterprises, so if you want to use appMobi and our cloud services but don't use any IAP or ads, then you get 100 free installs then $0.25 per MAU after that.
You can read more here: www.appmobi.com/pricing
Personally I like to develop with appMobi, but I may be a little bias :P
We work fairly close with Ashley to try and make sure everything is working on our exporter for directCanvas and when there are bugs I'd like to think we get a change into our build system fairly fast. Hope that helps you decide :D