Side project builders: how do you capture ideas that hit you mid-walk or workout?

Whenever I’m walking, exercising, commuting, or doing anything away from my desk, my brain suddenly starts firing:

- new project ideas,

- feature thoughts,

- “oh shoot, I should message X about Y,”

- or tasks I forgot about.

And since I'm not at my laptop, I end up:

- dropping quick notes into the Notes app,

- recording voice memos,

- or just forgetting things that felt important in the moment.

For people working on side projects:

How do you capture your ideas when you’re not sitting down to work?

Do you:

- use voice to text?

- send yourself notes?

- use an Apple Watch?

- maintain a quick capture system somewhere?

Curious to see what systems other builders rely on to keep ideas from slipping away.