It does and may be set via the following steps:
Press the spanner (wrench) icon in the top right. A popup is shown containing a switch, which will let you turn on spell checking for this document. When you turn spell checking on, any mis-spelt words will be underlined with a red dashed line. You can view spell correction suggestions by tapping on the underlined word. The suggestions will appear as menu items. Selecting a menu item will replace the mis-spelt word with the suggested word.
The language dictionary used for the spell check is indicated by the "Region format" in the "Settings" page of the device ("Settings"->"General"->"International"->"Region format").