Glide allows mobile apps to be created using spreadsheets. The spreadsheet is used by Glide as the data basis for the smartphone app and is automatically converted into an app after uploading. The layout of the mobile app can be adapted as desired. Glide also offers the integration of user registrations, payment functions and third-party tools such as Zapier or Google Analytics. Glide also provides a large template library in which you can choose from various pre-constructed application examples.
The company typeguard Inc. is based in the USA and presumably also stores all data there. The use of Glide is risky from an EU perspective after the Privacy Shield agreement was overturned.
Further information on Glide's data protection:
https://www.glideapps.com/privacy