Hi,
I'm looking for traffic sources that allow you to run CPA campaigns for mobile offers (i.e. pay per conversion and not per click).
Right now I know of propeller let's you do that. what other sources allow that?
Thank you! 
You should get in contact with some of them directly. I believe there are a few more that can do this but only on managed campaigns, rather than self-serve. If I remember right I think Adcash can do this, but not 100% sure.
yeah I'm looking for managed as well. let me know 
Check out reporo and mobads
Clickadu (uses the same backend as Propeller)
Hi there!
Did you hear about Hilltopads? We can be your traffic source, easily. We have dozens of WW traffic from direct publishers, waiting for your CPA campaigns. Also, we have a lot of targetings available, and our tech team has recently improved its anti-bot traffic filters.
Ping our affiliate manager, Helga, via Skype for further assistance. Her ID is OK HilltopAds.
Or feel free to PM me.
Cheers!
Hilltop good network - but they don't have such a model.
Only few networks has non managed CPA model. Mainly all of them managed, and managers will work with you only in case you have great convertion rate.

Reporo has CPA now
I tried Propeller, lot of fake traffic, they always change me AM, i know for some guys it works good, for me it was waste of money.
Clickadu works good for me meanwhile, eCPL very cheap, awesome AM.
Throwing our hat in the ring... we are one of the original mobile CPA networks, you will find references of Kimia on several threads in the forum, as we have over 10 years experience in the mobile marketing industry
If you want to learn more, just contact me via PM, skype: mlopezarranz (please mention you are coming from STM
) or write me at marina@kimia.mobi
Happy to help!