Not necessarily a big difference for E-Books, you will need a free app like Kindle or Kobo but magazines, on an app like Zinio, will be in full color. (never used a Kindle tablet so might be the same)
Today's color E-Reader/tablets are more robust and have better features than yesterday's E-Ink readers but that's because they are really just Android tablets with an OEM launcher on top specifically tuned for their products. Tablets, and more recently E-reader tablets, can also have more storage added in the form of micro SD cards. (S2 and newer Kindle HD tablets can have up to a 128 GB micro SD card)
Pros of a tablet over an E-Reader: (E-Ink type)
* You can generally do more on a tablet.
* You can listen to music while you read (and access the controls
from a drop down menu)
* Resolution is usually higher (Not always so check!)
* It is not locked to a specific site (IE: Amazon for Kindle, Barnes
& Noble for Nook) so you can use any reading app like Kindle, Kobo or Nook
* Generally has more powerful CPU if you play games
* You can change launchers if you don't like the stock one
* Most come with note, writing, spreadsheet and other software
* Usually shows as a drive when plugged into a computer
Cons of a tablet over an E-Reader: (E-Ink type)
* Not as good in bright sunshine (My S2 is OK with the brightness turned up)
* Generally the battery doesn't last as long as an E-Reader
(especially if the brightness is high)
* Need to be charged more often (E-Ink readers can go weeks on a single charge)
* A bit more expensive depending on size and memory
* Tablets are generally larger (8" to 12") so can be a bit more cumbersome.
(Although my 9.7" S2 fits in my jeans pocket with a slim case on it!)
I have been using tablets for years and have been through seven different types and sizes. My first was a Nook color (which I still have and probably still works) My last three were Samsung's Tab2 7", Tab S 8.4" and now my Tab S2 9.7" which I adore!