JotForm is a free online form builder which helps you create online forms without writing a single line of code. No sign-up required.
We believe that if one user has a question, there could be more users who may have the same question. This is why many of our support forum threads are public and available to be searched and viewed. If you’d like help immediately, feel free to search for a similar question, or submit your question or concern.
Since we can assist with only one issue / question per thread, I have moved your following questions to new threads.
http://www.jotform.com/answers/708312 - about coming back to finish the form
http://www.jotform.com/answers/708316 - about coming back to form after it was submitted
http://www.jotform.com/answers/708318 - about logins
In regards to the database, you can do that by setting up webhook on your form: How to Setup Webhook with JotForm
Basically you set the form to send the data to specific file on your server that goes through the data and saves it where and how you like it.
Do let us know if you have any additional details in regards to this, and we will be answering your other questions shortly.