Kiosk
8.0#1 in webhook management softwareFree planFree planAndroidiOSWebExtension
VisitKiosk suits readers who want a free PDF app across desktop, mobile, web, or a supported browser, with search and display options. It also fits people who want on-device PDF processing and annotation tools in the Chrome extension.
You want what its maker publishes above — check its page for the details.