Third-party keyboard apps have specific rules: they must not transmit keystroke data off-device without clear disclosure and consent, need to support the standard "Next Keyboard" switching, and must work without requiring full network access unless a feature genuinely needs it.
Commonly triggered by requesting "Full Access" for the keyboard without clearly explaining why, or by analytics code that logs typed content more broadly than disclosed.
"Your custom keyboard extension requests Full Access without adequately disclosing what user data is collected and why, per guideline 4.4.1."