Go to Settings > Security and toggle on Unknown Sources to allow installations outside the Play Store.
After extensive testing, these five PDF readers offer the best balance of speed, features, and reliability on KitKat. Pdf Reader Apk Download For Android 4.4.2
The PDF reader tried to load a modern web component (Chromium WebView) that doesn’t exist on KitKat. Fix: Switch to MuPDF or EBookDroid. They use native rendering engines, not web-based ones. Go to Settings > Security and toggle on