If this is your app, you can see how the app listing changes you're making affect your views and installs. You can even go months back in time.
Try App Store Analytics for your own Shopify app.
If it's a competitor, you can analyse their tactics and successes to come up with your own ideas to get more traffic and installs. You'll also get an email whenever they make a change, keeping you in touch with the market.
Track your competitors in App Store Analytics.