Should I empty the wrongly filled fields or leave as user has filled after validation message?

Question

In our mobile applications (intended for Android and iOS platforms), we have fields that should be filled by users.

If the user fills the field not in required format what should I do

1. show the validation message and empty the field, or
2. show the validation message and leave the field as the user initially filled it, letting him edit his old records?

Answer 1

Typing on mobile is a very arduous and unpleasant process, so we should try keeping it to a minimum.

Sometimes your users will have made just a small error that can be fixed by replacing or adding a character or two (typically they typed something instead of @ in an email address etc.). Sometimes they will have made a big error and they need to retype the whole thing. So unless you have a way of knowing or making an educated guess as to which type of error will be more common with your users and your type of data - it seems like there's no way of knowing. However, small mistakes are much more common by nature.

Even if we say that we have no way to know this, deleting an entire field on mobile is still much easier for the user than entering an entire field - you just hold the Delete key. So if we keep the data, those who would've preferred that we clear the field have a small price to pay for our decision, since the field is deleted easily. But if we clear the data, those users who would've preferred that we keep it, have a high price to pay - they need to retype everything.

Seems to me that keeping the data is definitely the safer way to go.

Answer 2

From a usability point of view, definitely keep their entry. There is nothing more annoying to users, in our experience, than clearing their entry on failing validation. They need to be able to see what they have done wrong, and if you clear it they are having to use their memory.

Answer 3

Why not provide a way for user to do both ? Data can be left intact as suggested by others and providing a small "X" button/icon ( similar to the magnifying glass icon usually seen in search boxes) at the end of text box to clear the whole thing if the user intends to.

Answer 4

Generally speaking, especially for text type input or textarea field, it is better to keep the existing text upon validation error. However, depending on your actual scenario, there may be other decision making steps that you might need to consider:

• If it is in a totally wrong format. Example you requested for numbers and the user fills up the field with alphabets, clear it and show error message. It is meaningless to keep input that you do not want to accept.
• If it is in a partially wrong format. Example you want users to enter a description about themselves, but clearly stated that URLs are not accepted, remove any URLs programmatically and save the input without showing any error message.
• If it contains sensitive information. Example user entered a wrong password. Clear it and show error message upon authentication failure.
• If you detect abnormal inputs such as extra POST parameters, clear the form but do not show any error message. If possible, redirect user to another page or log out the user.