We try to ensure that our applications do not fail and our users always find the way to do their tasks easily, but both people and systems fail. When any of these circumstances occur, what we must do is inform the user properly about the situation and provide useful information to solve what went wrong.

Errors are interruptions for the user and nobody likes things going wrong, but it is something that happens continuously in real life. We should try to handle these situations as humanly as possible, and we can try to turn a negative situation into an enjoyable experience for the user.

Here are some tips to create error messages:

• Humanize errors: Users do not speak the language of servers, nor do they understand codes, especially if we are talking about a mobile phone application. We should phrase the errors in the same way we would speak to another person. Avoid technical terms that could confuse the user and make the problem seem more important and complex to solve.
• Use proportional language: Not all errors are equally serious, and this should be reflected in the explanation of the error. The seriousness with which we express an error situation affects the users perception of the error. We must use language that is soft and reassuring in those errors that do not convey a serious application failure.
• Avoid interruptions when possible: Use interface elements to display the errors that match the severity of the problem. When we have to inform the user of an error that prevents the operation of the application, the error can interrupt the user and request an action in order to continue. For example, an application might not work due to a malfunction of the servers that support the application. However, errors that do not affect the overall operation of the application should be displayed locally and allow the user to continue with the rest of the application. Some applications allow the user to continue despite having a malfunction in some parts of the application. For example, an application might report poor internet access, but allow the user to continue browsing the local content or content that has already been loaded.
• Provide a solution if possible: Users will appreciate that the message, in addition to explaining what is wrong, tells them how the error can be solved. We can include tappable actions in the error itself, so that the user is guided to solve the problem from the error message. Guiding users in resolving an error will help make the experience more satisfying, reducing any feelings that an application is complex or requires prior learning.
• Allow a user to explore or cancel: Those errors that do not need to be solved straight away, should allow the user to explore and get further information, or undo the action to resolve the problem later. We can inform the user that a section of our application needs action by the user in order to function properly. Through a visible action the user can get more information about the problem to solve, but decide to fix it later. Keep the user navigation history when possible, so the users can recover the task they were doing previously.