Action Button
Point the Action Button at Offhand. Then a thought costs one press, even with the screen locked. Offhand is already in the picker. You only have to choose it.
The Action Button is on the iPhone 15 Pro and every iPhone after it. Those are the same phones that run Apple Intelligence, which Offhand needs to split a note into tasks, so there is no iPhone that has the button and cannot do the rest.
The microphone opens, and recording starts in the background before the app is even on screen. With the phone locked, the Lock Screen and the Dynamic Island show the capture while it runs: the mark, a clock counting from the start, and a Stop and a Cancel that work from the locked phone.
Say it the way you would say it out loud. “Call the dentist first thing, then pick up the dry cleaning this afternoon” is two tasks in two parts of the day. A task that names a clock time alerts you at that time. A task that names only a day waits quietly on that day.
After each capture, a receipt shows the words it heard. When it cannot find a task in what you said, it saves the note and says so. It does not invent one.
Siri already knows Offhand. Say “Start a note in Offhand”, “New note in Offhand” or “Take a note with Offhand”, and the same capture starts.
Back Tap gives you something physical to press on a phone without the button: open Settings › Accessibility › Touch, turn on Back Tap, then pick Add by Voice.
On an iPhone 14 or an iPhone 15, which have neither the button nor Apple Intelligence, Offhand still records and transcribes, and files each note as one task with the time it named. It does not split a note into several tasks, mark what they are about, or offer groups. Which iPhones run all of it, model by model.
Two more ways in belong to Pro, the optional subscription: the Control Center control and the Lock Screen button, each of which starts a note without opening the app. The Action Button does not, and is not going to.