Yes, with E-ink (it's name of the company who makes e-ink as well) you can read a book in the sun. The product E-ink was introduced as the best digital alternative for paper. And now in color, it supposed to be even a better alternative. However, an LCD eBook reader is always in full color, has better color experience, turns pages a lot quicker and is cheaper. An LCD-screen is about $100 cheaper than the e-Ink variant. And yes, you have to sit in the shadow with an LCD-screen to be able to read what is on the screen.
LCD is evolving as well. Nowadays you see the evolution of High-Definition LCD (HD-LCD) with extraordinary brightness.
Mobile phones with e-ink are a rarity. In 2008 the (Casio) Hitachi W61H phone was the first phone with e-ink (e-paper technology), but it never became a hit. Most phones use LCD.
Top Question List 7 - Compatibility of an eBook reader
Top Question List 5 - Color or Black and White screen of an eBook reader
Top Question List 4 - Price of an eBook reader
Top Question List 3 - Design of an eBook reader
Top Question List 2 - Multi-functionality of an eBook reader
Top Question List 1 - The hand-held eBook reader device