Three years have passed since Amazon last updated its flagship e-reader, and while this year’s Kindle lineup seemed focused on Amazon’s first color offering , the Paperwhite still got some welcome improvements . With a higher-contrast screen and snappier performance, the 12th-generation Kindle Paperwhite remains the best e-reader on the market. I tested the $199.99 Kindle Paperwhite Signature Edition, which is $40 more than the $159.99 basic Paperwhite. The screen and internals are the same,