The use case it is designed for is for shift workers who work x days on, y days off. So if you ask them "Are you going to be able to go to my wedding on July 15, 2012" they have no idea. This helps solve that problem.
Feed back as always is appreciated.
Great name and looks useful. Make it work on any mobile phone and it will be really useful. On my Samsung S8300, the submit button is invisible.
On the calendar, you should clearly label on and off days. It's not immediately obvious.
Your site mentions you've developed an algorithm. What does it do apart from adding days and accounting for holidays? :-)
We have that on our todo list.
Honestly, nothing else yet. The designer put the text in there. Trust me my algo is nothing like developing an algo for netflix recommendation or google search.
I second some of the other feedback here (saving details, better labelling of on or off days, .ics export).
One extra feature you might want to add: ability to check a date in the future without having to scroll through the calendar months. So, in your wedding example, I could put in my shift details, the start date, and the date I'm checking, and it would tell me whether I'm free or not.
My only comments are:
It should save what you enter, eg: I put 4 days on, 4 days off, and while it did show the right shift info, the fields reverted to 4 days on, 3 days off.
The date field would benefit from a date picker.
Out of interest, how (if at all) are you planning to make money from it?
1. I wanted to learn ruby + sinatra. This was just to see what I could build acting as the programmer + sys admin.
2. The designer and I both want to work together on bigger and bigger projects. This was a test to see if we could work together well and not hate each other at the end.
So there never was any plan to make money off of it. If you have any suggestions I'd be open to them.