Hosted Viewer
The server does the rendering. File size is not your device's problem.
Doconut SDK
Need this viewer inside your own app? The same engine is the Doconut SDK, with docs and samples at doconut.com.
No Account Needed
Nothing to configure. Drop the file and read it.
Doconut.app: Free Viewer, No Account
70+ extensions, no sign-up, files deleted after viewing. REST endpoints for upload and view.