There are several tools available that can help you generate keyword suggestions for your app. Here are a few options:

1. Sensor Tower: Sensor Tower is a tool that helps app developers optimize their app store listings. It provides keyword suggestions based on data from the Google Play Store and the Apple App Store.
2. App Annie: App Annie is a tool that provides market intelligence and data insights for app developers. It has a keyword tool that suggests relevant keywords based on data from the Google Play Store and the Apple App Store.
3. Mobile Action: Mobile Action is a tool that helps app developers optimize their app store listings. It provides keyword suggestions based on data from the Google Play Store and the Apple App Store, as well as data on app rankings and performance.
4. Google’s Keyword Planner: Google’s Keyword Planner is a tool that helps businesses create Google Ads campaigns. It can also be used to generate keyword suggestions for apps. To use it, you’ll need to set up a Google Ads account and enter your app’s information, such as the app name and description.
5. ASOdesk: ASOdesk is a tool that helps app developers optimize their app store listings. It provides keyword suggestions based on data from the Google Play Store and the Apple App Store, as well as data on app rankings and performance. It also has a keyword research tool that suggests relevant keywords based on data from the app store.

By using these tools, you can get a better understanding of which keywords are being used by your competitors and how well they’re performing. This can help you choose the right keywords for your app and improve its chances of being discovered in the app store.