OS	Fire OS 4 (Sangria), based on Android 4.4.2 (KitKat), Clean Pure Amazon Multimedia Experience
Chipset	Flagship Qualcomm Snapdragon 805 APQ8084 (28 nm HPm 2.5GHz Quad-Core 32-bit Krait 450 Processor with Adreno 420 GPU @ 600MHz) + World-First Dolby Atmos Cinema Sound DSP Engine
RAM	2GB RAM
Storage	16GB / 32GB / 64GB
Display	8.9 inches • 2560 x 1600 pixels (16:10, Giant 8.9" 2.5K UltraX 2560p IPS LCD Display, 339 ppi)
Main camera	Pro 8.0 MP Rear Camera with f/2.2 Large Aperture, LED flash & 1080p Video: 8.0 MP 1/3.2" f/2.2 Large Aperture Main (autofocus, Electronic Image Stabilization EIS, 1080p@30fps Full HD video recording) with High-Power LED flash
Selfie camera	Flagship 1.3 MP Front Camera for 720p HD Video Calling & Skype (720p@30fps video)
Battery	Monumental 6000 mAh Colossal Monster Battery! (Powers over 12 hours continuous reading, web surfing & video / 800 hours standby / 60 hours audio!), 10W Fast Charging via Micro-USB (9W Amazon PowerFast in box!) + Low-Power Reading Mode (delivers up to 18 hours of reading life!) • Non-removable Li-Ion (6000mAh Monster)
Weight	375 g (13.23 oz)

Latest Amazon Fire HDX 8.9 user agents:

User Agent	Browser	Platform
Mozilla/5.0 (Linux; Android 5.1.1; KFSAWI) AppleWebKit/537.36 (KHTML, like Gecko) Silk/108.18.4 like Chrome/108.0.5359.220 Safari/537.36	Mobile Silk 108	Fire OS 5Fire HDX 8.9
Mozilla/5.0 (Linux; Android 4.4.3; KFSAWI Build/KTU84M) AppleWebKit/537.36 (KHTML, like Gecko) Silk/44.1.81 like Chrome/44.0.2403.128 Safari/537.36	Mobile Silk 44	Fire OS 4Fire HDX 8.9
Mozilla/5.0 (Linux; U; Android 4.4.3; en-us; KFSAWI Build/KTU84M) AppleWebKit/537.36 (KHTML, like Gecko) Silk/3.68 like Chrome/39.0.2171.93 Safari/537.36	Mobile Silk 3	Fire OS 4Fire HDX 8.9