Free version with in-app purchases.
- Universal app for all devices.
- prweb.com : Press releases works (just breaks even for $5 product)
- Target Mac related sites for press releases.
Wasted money on junk keywords. Use Double Click site to check traffic stats before spending on advertising on sites.
Be wary of people contacting you (harvesting email on your sales page) for ad placement on their site. These are lousy sites with no traffic.