The e-reader era just arrived, but now it may be ending.
Dedicated devices for reading e-books have been a hot category for the past half-dozen years, but the shrinking sizes and falling prices of full-featured tablet computers are raising questions about the fate of reading-only gadgets like Amazon.com Inc.'s AMZN +0.45% original Kindle and Barnes & Noble Inc.'s BKS -2.00% first Nooks.