The below tool helps to get all installed apps in hosted web. You can see below screen shot where you need to enter the host web url in the text box and click on Get Apps button.
It will display all the Apps deployed in that particular host web in a grid with Title and App web URL(Appwebfullurl).
Please check the below powershell script where you can save it as getapps.ps1 and run it.
Devendra Velegandla is a five-time recipient of Microsoft's Most Valuable Professional (MVP) award (2014-2019) for Office Apps and Services, Office Servers and Services MVP and SharePoint Server. He received the MCC award for his contributions in Microsoft MSDN/TechNet forums. He loves sharing articles, videos, and tutorial on SharePoint and Office 365.