Hi there, based on my experience, you can increase your app ranking on the Play Store with the following methods:
Keywords optimization
Keywords play a very important role in SEO and so do they in Google Play Store’s ranking algorithm too. Follow these 3 key tips when choosing your keywords:
[ul]
[li]Look for keyword relevant to your app[/li][li]Choose keywords with lower difficulty scores[/li][li]Choose keywords having highest traffic scores[/li][/ul]
You mentioned that no matter how many keywords u add into the description nothing changes, maybe those keywords are too competitive, hard to rank for.
Optimize app title
If your app title has the right keywords related to your app, it increases the chances of getting discovered by users in search. So be sure to use your main keyword in the app title, which can increase your app ranking by 10.3%
Place the important keywords in app description
Google Play gets the keywords for an app from the app description. This field has 4,000 characters, so there is plenty of room to add your keywords. Keywords appearing within the name of an app itself usually allow the app to rank higher for those keywords.
Get Positive app reviews
Your app’s review is one of the most important factors influencing its ranking in the Google Play lists and search results.What’s more,88% users trust reviews as much as personal recommendations.
Get 4/5-Star ratings
Your app’s rating also play an important role inPlay Store Ranking algorithm. It’s also one of the key metrics that the editorial staff looks for when curating apps and games.
Jain says reviews and ratings are “a very strong signal for Google,” so maintaining an app rating average above 4.0 out of 5 is mission critical.
Google+ sharing
This is one of the unique factors that influences an app’s ranking in the Play Store, and can be used by developers looking to increase ASO.
Increase Incoming links
Like SEO for normal sites, more internal link to your app page will help in improved ranking.
Hope those methods are useful to you.