Esto lo he sacado del support de SwiftKey :
Back-up - Worried about losing your learned words? SwiftKey 3 now supports the Android Backup Service*, meaning your learned language data is saved by Google into the cloud if you opt in. Never lose your personal dictionary again! (*if this service is enabled on your device)
Es en el cloud, tienes que habilitar el servicio. No busques en SwiftKey, es en Ajustes cuando te encuentras en tu Homescreen.
Saludos
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