While there is not a spell checker, you can use your browser's spell checker options.
Turning on Spell Checker in your browser
Steps for Google Chrome (recommended browser)
Go to Settings.
Scroll all the way down and click on Advanced Settings.
Under Privacy, find out “Use a web service to help resolve spelling errors”.
Turn on the feature by tapping on the slider. The slider will turn blue when the spelling checker is turned on.
Steps for Firefox
Select the “Menu” button located at the upper-right corner of the screen, then choose “Options“.
Scroll to the “Language” section.
Select “Check my spelling as I type” if you want to turn spell checker on. Uncheck it if you wish to have it off.
Steps for Internet Explorer 11
Select "General" from the PC Settings menu on the left side of the screen
Scroll down to the Spelling section.
Set the "Highlight Misspelled Words" slider to the "On" position to make Internet Explorer identify misspelled words by placing a red squiggly line underneath them.