Predictive text on your phone’s built-in keyboard learns mostly on the device. The iPhone keyboard learns your words locally, and Gboard improves its suggestions with federated learning, which sends model updates to Google rather than the text you typed. The bigger privacy risks are elsewhere: third-party keyboards given full or network access, searches and voice input sent to servers, and AI writing features that upload your text to rewrite it.
How does predictive text work? #
A keyboard’s prediction engine is a small language model. As you type, it looks at the words before the cursor and estimates which words are most likely to come next, then shows the top three. Autocorrect uses a similar model to guess which word you meant from the keys you hit.
Two layers make it personal:
- A general model trained by the keyboard’s maker on large amounts of text, shipped with the keyboard.
- Your personal layer, learned from what you type: names, slang, your usual phrases, the words you keep correcting back.
Because the model is small and runs on the phone, suggestions appear instantly and work offline. The privacy question is what happens to that personal layer and anything else the keyboard sees.
Does Gboard send what you type to Google? #
Not for training its predictions, according to Google’s design. Gboard uses federated learning, which Google described in 2017: your phone stores information about what you typed and which suggestions you tapped, improves a copy of the model locally, and sends only that model update to Google over an encrypted connection. A cryptographic protocol called Secure Aggregation means individual updates are averaged with many others before Google can see them.
Some things do go to Google’s servers by nature:
- Searches you run from Gboard’s search features.
- Voice typing, depending on your language and settings, since some voice recognition runs in the cloud.
- Anything you type into a Google app or website, which is the app’s doing, not the keyboard’s.
Gboard’s settings include a Privacy section where you can review these options.
Is the iPhone keyboard private? #
Apple’s keyboard learns the words you use on the device, and that learning isn’t sent to Apple for prediction purposes. If suggestions have gone strange, or you want to wipe what it learned, go to Settings > General > Transfer or Reset iPhone > Reset > Reset Keyboard Dictionary.
Dictation is separate. On supported iPhones and languages much of it happens on the device, but Apple Intelligence and Siri features may send some requests to Apple’s servers. Writing Tools, which can rewrite or proofread text in most apps, runs on the on-device model for most requests and uses Apple’s Private Cloud Compute for heavier ones.
What about third-party keyboards? #
This is where most keyboard privacy risk lives.
- On iPhone, a third-party keyboard can’t use the network unless you turn on Allow Full Access for it. With full access, the keyboard’s developer can transmit what you type. iOS always switches back to the system keyboard for password fields.
- On Android, any keyboard you install can see everything you type into it, and Android shows a warning when you enable one that it may collect all the text you type, including passwords and card numbers.
| Keyboard | Learns on device | Can send your typing? | Notes |
|---|---|---|---|
| iPhone keyboard | Yes | Not for predictions | Dictation and Apple Intelligence features have their own rules |
| Gboard | Yes, plus federated learning | Model updates, not raw text, for predictions | Searches and some voice typing go to Google |
| Samsung Keyboard | Yes | AI writing features may use cloud processing | Galaxy AI settings let you keep processing on the device, with some features then unavailable |
| Third-party keyboard with full/network access | Varies | Yes, if the developer chooses | Read its privacy policy |
| Third-party keyboard without full access (iOS) | Yes | No | Fewer features, such as no sync |
Do AI writing features in keyboards send your text? #
Often, yes. “Rewrite this”, “make it more formal”, grammar checking and tone suggestions need a much bigger model than word prediction. Some run on the device, like parts of Apple’s Writing Tools and some Gemini Nano features on recent Android phones. Many others, including popular grammar keyboards, send your text to a server to process it.
The rule of thumb: if a feature rewrites whole sentences or paragraphs, find out where it runs before using it on anything private. Look for wording like “processed on your device” in the feature’s settings or help page, and check the app’s store listing using our guide to reading AI app privacy labels.
How do you make your keyboard more private? #
- Stick with the built-in keyboard for sensitive typing, or remove third-party keyboards you don’t use.
- Turn off full access for any iOS keyboard that doesn’t need it.
- Review Gboard’s Privacy settings if you use it, including voice input options.
- Reset the learned dictionary occasionally if it has learned things you’d rather it forget.
- Check AI writing features before using them on medical, legal, financial or work text.
- Keep your phone locked. Predictions can surface names and phrases to anyone holding your phone.
How can you rewrite a message privately? #
If you like AI help with wording but not the idea of sending your drafts to a server, do the rewriting in a local model instead of a cloud keyboard feature. Personal LLM runs open models such as Qwen 3.5 and Gemma 4 on your phone’s chip with no account, and your chats never leave the device.
- Write your draft in any app and copy it.
- Paste it into a chat with a system prompt such as “Rewrite my messages to be clear and friendly, under 80 words, same meaning.”
- Copy the result back.
It’s one more step than a keyboard button, and nothing about the message, whether a tricky text to a relative or a complaint to your landlord, reaches a server. For longer work drafts and what happens to text pasted into cloud chatbots, see is it safe to paste emails into ChatGPT. For everything else that can leak from a phone, see what on-device AI keeps private.
Frequently asked questions #
Does my phone keyboard send what I type to the company? #
The built-in iPhone keyboard and Gboard learn predictions on the device and don’t upload your raw typing for that purpose. Searches, some voice typing and AI rewriting features can send text to servers. Third-party keyboards with full or network access can send anything you type if the developer chooses.
Is Gboard safe to use? #
For everyday typing, Google’s design keeps what you type on the phone and sends only model updates for training predictions. Searches and some voice input go to Google. If you want the least data leaving your phone, review Gboard’s Privacy settings.
Should I allow full access for a keyboard on iPhone? #
Only if you trust the developer and need a feature that requires it, such as cloud sync or online lookups. Full access lets the keyboard transmit what you type, so read its privacy policy first.
How do I reset predictive text on my iPhone? #
Go to Settings > General > Transfer or Reset iPhone > Reset > Reset Keyboard Dictionary. This clears words and patterns the keyboard has learned and returns suggestions to their defaults.