By default, an e-mail containing the captured image is sent to your email address every time it is captured on schedule. However, if you'd like to disable emails from being sent, you can uncheck this checkbox. Captures will continue to happen on the schedule specified, the only difference is that an email won't be sent for these captures. To view the captured image, you can sign back into blitapp.com and view them on the history page, or you can set up an App to get them uploaded to your Cloud.
You can configure the default settings of your captures, like sending an e-mail or not, under Account.