App Distribution on NON-Google-Play markets

Hello all,
Although Google play is very popular for promoting android apps I am interested to know;
1. What other app markets can perform well for Android app distribution?
2. Is their compliance restrictions are softer than Google's.
3. Is there anyone who is specializing in selling PPI traffic for apps which are hosted on those markets?
Kindly advise...

Hmm i think a PAD submitter will help you get that done.

I have a list of 13 app stores that I submit to besides Google Play. I just started deploying to these stores but it seems promising so far, about an extra $1-2 per day per app in these very early stages. There are quite a few big alternative stores such as Amazon, Yandex, Samsung, SlideME that I think are worth publishing on. There's more but those were what just came to mind.

In terms of compliance they all seem to be fairly restrictions free. I use AirPush ads in my non Google Play versions and I haven't had any flak for that yet.

As for the 3rd point I can't help with that, I haven't done any paid marketing for my apps yet.

Do you think it is possible to buy PPI traffic from regular ad-networks to these alternative markets in which my apps are hosted? from what I see they are all just working with Istore and Google play...