The Nielsen/Norman group recently published Checklist for Designing Mobile Input Fields featuring a quick reference of what you should review when designing for mobile.
![A Checklist for Designing Mobile Input Fields via Jennifer Blatz UX design](https://www.jenniferblatzdesign.com/blog/wp-content/uploads/2015/07/Checklist-for-Designing-Mobile-Input-Fields.png)
Text version of checklist of 14 guidelines to follow for mobile input field UX
Should it be there at all
- Is this field absolutely necessary?
Description
- Is the label above it? (Not inside, not below)
- Is the field marked as required (*) or optional?
- Have you removed any placeholder from inside the field?
Visibility
- Is the field big enough so that most possible field values are visible?
- Is the field visible in both orientations when the keyboard is displayed?
Filling it in for the user
- Do you have any good defaults for this field?
- Any history available?
- Frequently used values?
- Can you use the phone features (camera, GPS, voice, contacts ) to populate it?
- Can you compute it for the user based on other info (e.g., state based on zip code, coupon field)?
Typing
- Do you support copy & paste into the field?
- What is the right keyboard for this field?
- Can you make suggestions/autocomplete based on the first letters typed?
- Do not autocorrect for names, addresses and email addresses.
- Do you allow typos or abbreviations?
- Do you allow users to enter it in whatever format they like? (e.g., phone numbers credit cards)
- You can autoformat it for them.