Sumi
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Sumi for iPhone · iPad · version 1.0
One app, one library. Sumi comes from the App Store and covers iPhone and iPad under the same Apple Account. Install it on either first — a note written on one is searchable on the other, with the same index, the same ranking and the same key.
iPhone and iPad
From the App Store, the only place an iPhone app can come from. The same app covers both devices under the same Apple Account.
Download on the App StoreMaking two devices one library
Each device keeps its notes in its own folder until you say otherwise. To share them, turn on iCloud Drive in Settings on one device; the files move into your own iCloud, and the other, signed in to the same Apple Account, is then looking at the same folder. The switch is reversible, and it is the only setting there is.
The key that seals the notes travels separately, through your iCloud Keychain. Whichever device you open the app on first makes it; the second finds it there. So before opening the app on the second device, make sure it is signed in to the same Apple Account with iCloud Keychain on — a device that cannot see the key makes one of its own, and the two libraries will not open each other's notes until that is sorted out.
If a device shows an empty library
If the app opens on the second device but shows an empty library beside notes you know are there, that device has the files and not the key: check that iCloud Keychain is on for both devices, then quit and reopen.
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