Yes. Reji uses iCloud to sync between devices. It means your data will be stored in your own iCloud.
You must be signed in to the same Apple ID on both devices. Then just open the app on a new device – Reji will automatically load data from iCloud. It can take some time until your decks appear.
Please note that there should be enough storage left in iCloud. Sync for Reji should be enabled in your iCloud settings. It also must be enabled in the app settings as shown below:
