You can indicate that an error occurred using haptic feedback. It can be useful for long-running tasks that fail, like page loads or downloads. But you can also use it as errors occur like Twitter does when reaching the character limit.
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A reminder that the more modes we use to convey important information, the more sure we'll be that it will be perceived by all our users. Consider a combination. of color, icons, messages, sound, haptics, animations, etc.
An alternative layout for large font sizes can be provided with Auto Layout by having three sets of constraints (common, default constraints, and alternative constraints) and activate/deactivate them depending on the content size category.
Potential benefits from grouping logical pieces of information and moving buttons to custom actions: reduce redundancy (by removing repetitive controls) and reduce cognitive load (by making easier to know what item will be affected by each action)
