How account and sync works

Left syncs your own Ahead dates, habits, streaks and Aims between your iPhones automatically. If you are signed in to a Left account (Sign in with Apple), they sync through that account, which also holds your profile, username, friends and shared dates. If you are not signed in, they sync through iCloud. Timing depends on the network, cloud service availability, and whether the previous device finished syncing.

What signing in does

You can create an account when you open Left for the first time, or later from Settings → Account → Sign in.

Left uses Sign in with Apple. Signing in creates your Left account, which stores your profile, username, friends and the dates you share with them, and syncs your own dates, habits, streaks and Aims across the devices where you sign in with the same account.

What syncs

When you are signed in, Left saves account-backed data in the cloud, including:

1. Your name.
2. Your profile photo or profile symbol.
3. Your username.
4. Your friends and friend requests.
5. Shared friend data such as Joint Ahead dates and shared Since invitations.
6. Your Ahead dates.
7. Your habits, streaks and Aims.

Once the data is in the cloud, signing in on another device should bring it across automatically. If you are not signed in to a Left account, your Ahead dates, habits, streaks and Aims sync through iCloud instead. Both iPhones need to be signed in to iCloud with the same Apple Account. Sync timing can vary depending on network connection, cloud service availability, and whether the app has had time to finish syncing.

What does not sync

Some preferences are device-specific and may not follow your account.

For example, app appearance choices, local display preferences, selected layouts, and other device-level settings can remain on the device where you set them. If something looks different on a second device, check the relevant Settings section and adjust it there.

How to sign in on another device

On the other iPhone:

1. Install Left.
2. Open the app.
3. Sign in with the same Apple account, either during first launch or from Settings → Account → Sign in.
4. Keep the app open for a moment so cloud data can load.

Your account data should appear after sync completes. If you delete the app but already had an account, signing in again should normally restore your cloud-backed data, but this cannot be guaranteed in every situation because cloud sync depends on service availability and the previous data having synced successfully.

Account settings

Go to Settings → Account to manage your account.

From there you can:

1. Update your name.
2. Choose a profile photo or profile symbol.
3. Set or change Your username.
4. Sign in or Sign out.
5. Delete account.

Your username is unique and lets other Left users find you. It uses lowercase letters and numbers.

Deleting your account

Delete account removes your Left account and related cloud data from Left's systems. It can take time for deletion to complete across all systems.

Deleting your account does not remove data that is already stored locally on the device. If you want to remove local app data too, delete the app from the device after deleting the account.

If you only want to stop using account sync temporarily, use Sign out instead of deleting the account.