When you run the tool it displays it gives you the number of errors, and screenshots of the pages for all those errors. Although it is in beta spellr works well and its very fast. In beta period the scanning is limited to 500 pages, but it will scan more pages once it comes out of bets. You can click on the screenshots to see the spelling mistakes, it also provides suggestions for correct words.
It also has plans to monitor grammatical errors in the future but that won’t be a free option i guess. The free scan service is made available to small websites, others have to pay. It can also monitor the web pages for spelling errors.
At the moment it is picking lot of words as errors, like blog, online, hopefully they will update their dictionary by the time they will launch publicly. There is an options to add words those are not errors to your word dictionary but that is not working at the moment. Overall it is a promising service for checking spelling mistakes in webpages. Thanks Techcrunch for the invite.