What are the Amazon Kindle User Agent strings?

Question

What are the valid Amazon Kindle User Agent strings?

Are they different for each model of the kindle?

Update: just got this one off the new wi-fi only kindle:

Mozilla/5.0 (Linux; U; en-US) AppleWebKit/528.5+ (KHTML, like Gecko, Safari/528.5+) Version/4.0 Kindle/3.0 (screen 600x800; rotate)

Answer 1

From Marco Arment:

Mozilla/4.0 (compatible; Linux 2.6.10) NetFront/3.3 Kindle/1.0 (screen 600x800)

From other research, Amazon increments the Kindle/n.0 version number depending on the Kindle version (i.e., the Kindle 2 is Kindle/2.0).

Edit

From Device Atlas, currently valid UA strings are the following:

Mozilla/4.0 (compatible; Linux 2.6.10) NetFront/3.4 Kindle/1.0 (screen 600x800)

Mozilla/4.0 (compatible; Linux 2.6.22) NetFront/3.4 Kindle/2.0 (screen 600x800)