Android
Turn Auto-capitalization On or Off auf Android
Auto-capitalization is a Gboard text correction feature that capitalizes the first letter after a sentence-ending punctuation mark or line break. It works independently of autocorrect and spell check, so turning off other correction features won't disable it on its own.
This behavior can get in the way when you regularly type lowercase identifiers, code, usernames, or specific formatting that shouldn't be touched. Since the correction happens as you type, it can also interfere with fast typing if it capitalizes letters you already fixed manually.
Where to change it
The option lives inside the keyboard settings, not the general typing settings. Follow this path:
Tap on Settings ➔ Tap on System ➔ Tap on Keyboard ➔ Tap on On-screen keyboard ➔ Tap on Gboard ➔ Tap on Text correction ➔ Enable or disable Auto-capitalization
Toggling it off stops Gboard from capitalizing the first word of a sentence automatically; toggling it back on restores the default behavior. No restart is needed, the change applies the next time you type.
If capitalization issues only happen in one specific app, check that app's own text input settings first, since some apps override keyboard-level corrections.