Helpful sites or apps
Grammarly is an extremely useful tool, I think it's actually more in depth than Spell checker. It reveals how extensive your vocabulary is in comparison with other users among other things.
Other writing sites
Poem of the week.co.uk: It's a place for poets to display four poems of their choice which will be changed weekly for a month, and then placed in an archive. If you are a fiction writer, then you can display stories on the same principle.
http://www.bankholidaydates.co.uk/GreatBritain/1852.aspx: Bank holidays
http://elizabethashworth.com/2013/05/20/1399/: History of Hornby Castle