AppSales - Find the best Android apps and games from Google Play that are currently discounted or free for a limited time
AppFollow - AppFollow is an integrated solution that makes monitoring, analyzing, and elevating your app's reputation easy.
Fnd - Browse Apple App Store and iTunes on the Web
appfigures - Cross-platform app store analytics for all of your mobile apps.
TheAppStore.org - Find apps by rating, price, category, updated date and more
AppReviewBot - Get new iOS App Store and Google Play Store reviews directly in Slack, Microsoft Teams or Mattermost as soon as they happen. Unlimited apps, every country.