What every page starts on is in More → Assistants → Write it uses. It is Apple's cloud unless you change it (the model on your iPhone where there is no cloud). Choose Last used there, and every page starts on whichever you picked last beside Write it.
| Choice | Where it runs | Needs | Good for |
|---|---|---|---|
| On this phone | On your iPhone. Nothing leaves it. | Apple Intelligence (iPhone 15 Pro or newer) | New routines from a sentence |
| Apple's cloud | Apple's Private Cloud Compute, from inside the app | iOS 27 and Apple Intelligence | Everything: new routines, changes, triggers, runs |
| Apple's cloud, with the web | Apple's Private Cloud Compute, through Shortcuts | The free Routine Run Ask shortcut | Routines that need real how-to links |
| ChatGPT | OpenAI, through Shortcuts | The shortcut, and the ChatGPT extension on in Settings → Apple Intelligence | If you prefer ChatGPT |
| ChatGPT, talk it through | OpenAI, through Shortcuts, as a chat | The same | Working it out in a conversation first |
The three that go through Shortcuts are listed once the Routine Run Ask shortcut has run on this iPhone. Before that the app has no way to know it is there, so they stay out of the list; get it from More → Assistants → ChatGPT and the web.
On this phone writes new routines only. Asked to change one, it mixed up steps in ways that were hard to notice, so changes go to a bigger model.
Which one you get first
- iOS 27: Apple's cloud. Nothing to install, and Shortcuts never opens.
- iOS 26: on this phone for a new routine. For everything else, the shortcut.
You only need the shortcut if you want the web or ChatGPT. The app offers it when you choose one of those. The bridge is offered after that, and only if you want answers without Shortcuts opening.
Only on this phone
The first run asks where AI works: in Apple's cloud, or only on this phone. Choose only on this phone and nothing you type is sent anywhere, and the app keeps to that. Where the phone's model cannot do something, such as changing a routine, Write it goes grey and says so, rather than sending it to the cloud. You can still choose Apple's cloud beside Write it for that one question, or continue with your own assistant. Change it for good in More → Assistants → Write it uses, or in Where AI works from the first run.
Where your words go
- On this phone: nowhere.
- Apple's cloud: to Apple's Private Cloud Compute. It is used to answer and not kept, and nobody at Apple can read it.
- ChatGPT: to OpenAI, under OpenAI's terms.
- Continue with an assistant: to whichever app you send it to.
What is sent is your sentence and, when you asked about one, that routine, step or run: its names, descriptions, lengths and notes. Nothing is sent until you press a button.
Apple's cloud has a daily limit
Apple allows each person a number of questions a day, counted on their iCloud account. When you are close, the page says so in orange. When it runs out, the page says when it comes back, and may offer Ask for more, which is Apple's own offer through iCloud+. Until then, choose another writer beside Write it.