This has been a year of tech experimentation for me. I gave up my clunky-but-serviceable Kindle Touch in favor of a slick, front-lit Kobo. I relegated my iPad 2 to work functions, and picked up a more ergonomic iPad Mini for home use. And I experimented with various apps in search of a perfect reading platform. I didn't find it. It is with mixed feelings that I declare the Kindle app the 'winner,' and give up on iBooks. Here's why: The Kindle can sync personal documents. That's it. That's the killer feature iBooks and Kobo and all the rest lack, and it...