What are the best practices of designing a validation message on an iPhone App?

Question

I am working on designing an iPhone app and I need to know which validation message style is the most recommended for the forms included.

I don't prefer to use a pop up window i need something that keeps the user on the same page with minimal distraction.

Answer 1

I personally have seen US2FormValidator used in a couple of iPhone apps and its pretty slick. I'm not sure I personally agree with the default icon choice for the error icon, because tends to look a bit like if I touch it, it will delete/clear the field.

I think that library is a great improvement over the default of just popping an alert when something doesn't validate.

Here's some additional usability benefits:

• Validation can occur as the element is blurred without interrupting the user's flow. (Don't have to wait for submit to know what they entered is invalid).
• Errors are visually-related to the field being validated. As opposed to in an alert where it tells you the name of the field, you can actually see which field is invalid.
• User may not need the detailed message to know they did something wrong -- with a solution like this they have the option (but aren't forced) to read any detailed message before being able to correct the error themselves.

Here's a video I found demoing it in action as well.