The best waterproof tablet for Android is the Samsung Galaxy Tab Active 8.0. It is waterproof, dustproof, survives drops, and comes with a one-year warranty.
Update October 2017:
The Samsung Galaxy waterproof tablet does not seem to available on Amazon anymore.
It looks like the only waterproof tablet available is the WinBridge S933, which runs Android.
The Details: Waterproof Tablets
Samsung’s ruggedized version of its flagship Galaxy tablet is protected by protective silicone edging and a sturdy internal frame. It has an impressive IP67 rating, which means it has complete protection against contact from dust and is safe in up to 1m of water immersion.
The Samsung Galaxy Tab Active 8.0 has an 8″ daylight-readable LCD screen that has a max resolution of 12800 x 800, which is a little low compared to commercial tablets. Its battery life lasts around 12 hours, which will get you through an entire workday. It has a 1.2 GHz Qualcomm processor and 16 GB of memory.
Computerworld praised the Galaxy Active 8.0 for being light (1lb), comfortable to grasp, and easy to write with. It includes a C-Pen stylus.
LTE is a no-go, as the Galaxy Tab only runs on Wi-Fi and uses Android 4.4 KitKat.
The Samsung Galaxy Tab Active 8.0 is available on Amazon for around $540.
Active 8.0’s, but its Core i7 4600U processor is more powerful. The Getac also has a tethered stylus, a barcode scanner, USB 3.0, and an HDMI port.
The Getac F110 is available on Amazon for around $3,880.