Each 1krNote plan covers a number of phones at the same time: 1 phone on Free, Starter and Pro, 3 phones on Max.
When you sign in on another phone and all your phones are already in use, the app asks Use 1krNote on this phone? "All phones your plan covers are signed in. If you continue, the phone you used least recently is signed out."
- Tap Use this phone to move to the new phone. The old phone is signed out; its notes stay on it.
- Or cancel, and sign out on the phone you don't use any more first (Account → Logout), or remove it on the website under Phones.
Your notes don't move by themselves. They're stored on each phone, not in your account. To take notes to a new phone, share or copy the ones you need before switching.
Moving to a new phone is limited to twice in 30 days, see "Moved to a new phone twice in the last 30 days".