Last year back in November, I posted
this thread with pics, of how I utilize my Apple iPad with my Tyros 4 keyboard. Since then I discovered an even better very simple and inexpensive ipad stand setup to better secure the iPad on the Tyros 4, and also further protect both the iPad and Keyboard from getting scratched or damaged.
Fully Ajustable Three Wire (with protective plastic coating) Display stand for books, cookware, electronics; Set of 2 - Black. cost: $7.95.
This light as a feather stand is extrtemely versatile for viewing the iPad just about anywhere in either landscape or portrait mode and at any angle, but better yet it works great for viewing music atop my Tyros 4 keyboard as well. It's fully coated in plastic to reduce any possibility of scratching either the T4 or the iPad as well as the plastic keeps the stand from sliding as well. I highly recommend this stand and use it exclusively for all my iPad stand needs.
The iPad typically sits next to me when I perform and easily & conveniently with one hand, placed on and off the stand at will, whenever I want to view the T4's screen.

Here are pics I took of my iPad with stand setup on my Tyros 4 keyboard, shown in both portrait and landscape modes.
Portrait Mode: