AppStack is a mobile advertising company that helps businesses get customers through their "Promote" platform. Some key points: - Founded in 2011 and has received recognition from Google Ventures, TechCrunch, and other publications. - Promote allows businesses to create mobile-optimized websites and run targeted Google AdWords campaigns to get customers through click-to-call ads. - They claim higher conversion rates than industry averages and provide real-time reporting and call tracking to monitor performance. - The pricing model is $99 per month for the platform, $100 minimum ad spend per month, and 20% of ad spend goes to AppStack for management and support.