Whenever you talk about your app online, be sure to add the link to the app store page where users can download it, or to the web app (mobile site) so it can be easily found by anyone looking for it or coming across it by chance.
Post and promote your app on well known blogs via a targeted blogger outreach, this way you'll also get extra promotion to larger audiences.
App Install Ads
You can also promote your app by using app install ads, by setting them directly from the AppsBuilder dashboard if you wish.
Also, you can use them via your social media profiles. Here's a list of app install ads guidelines per social network:
Facebook - https://developers.facebook.com/
Twitter - https://dev.twitter.com/
Google - https://support.google.com/adwords/answer/6309967?hl=en&rd=1
In general, conversions from install ads are easily trackable, allowing you to measure the performance
of your ad campaigns and adjusting your strategy accordingly.