Our company has a new App Submission/Promotion/Reporting Tool for Android developers. It's free and we don't take any share of dev revenue. We believe in supporting independent developers the best way we can and actually we're trying to find ways to get in front of developers to discuss our product and hopefully get them on the platform.
This is a copy-paste of a previous answer I think could help you out as well :
Can't tell you about the 'where', but as per the 'how' I would suggest you adopt the 'feedback loop' mindset where instead of pushing to sell your product, you do all you can to involve your potential customers in the product development process.
The key psychological element here is that by getting their feedback and actually implementing them, you create a sense of 'belonging' in the marketplace toward your upcoming product, which will ultimately be of massive help during your launch.
In other words, don't approach the market as if you had a finished product, approach it as if you had a rough first draft you want them to improve (note that this is very hard to do, you have to put your ego on the shelf ; ).