This page outlines recommendations for designing and building useful CommCare applications. These are compiled from collective experience in app construction and are only recommendations. Individual projects could vary substantially and the overall best practice is to go through extensive user testing and piloting to identify and correct language, media, or work flows that are confusing.
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Take advantage of calculations in forms to minimize errors. For example, if you are asking for a birth date, add a label afterwards that shows the calculated age. This may highlight an error in date entry if the age appears different than what the user expected.
Use labels to force the user to stop and verify their information. You can add a label that shows the user data they entered and encourages them to verify if it is correct (see Common Logic and Calculations ).
Use groups to prevent writing the same display logic (and having to update it) for related questions. Groups also make it easier to manage large forms in the designer (see the Beginner's Guide)
Consider including a success/you're done with the form label as your last question. This can be particularly useful on J2ME phones by giving the user an opportunity to correct any errors and make it clear to the user that the form is ending..
Don't try to do too much in one form. If you make a simple form that is easy to use it has a higher probabilty of success than a complex one that tries to tackle too much.
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Validation conditions should always be accompanied by descriptive constraint messages that will clearly inform the user what they need to correct. You can also add audio to constraint messages. For example, you may want to put a limit on a birth date to make sure the user doesn't accidentally put a date in the future. But if you don't put a constraint message the user may not understand why their answer was not accepted. This can be very frustrating for the user.
You want to be careful about your validation - if a user enters data in the field that doesn't fit your validation rule, this could prevent your app from being used. Make sure that your conditions are realistic and consider allowing an extra margin on your allowed values to permit extreme cases.
Display Logic
You can make very "smart" display logic but it is critical that the trainers and field staff understand that logic very well. Otherwise they, along with the users, may be very confused by why certain questions show up in some cases but not others.
Required Question
Required questions prevent the user from moving forward in the form without entering or selecting a value. Be careful when specifying a question is required - if the user of the application cannot determine the value for a particular question (ex. they are transcribing from a paper form and the particular value is not filled in), this can prevent them from submitting any data. If necessary, you can add a follow-up question that asks why a particular value was blank.
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