External Drives (USB etc): These are generally safe for storing your data but performance may be slower depending on the type of drive and connection it uses. For sharing data between computers, this is the recommended option, just be sure to shutdown Geneious and safely eject the drive before unplugging the drive. External drives are also great for storing backups in a separate location.
Cloud Storage (Dropbox, Google Drive etc): We strongly advise against storing Geneious data directly in a cloud storage folder because data can easily become corrupted. Cloud storage is fine for storing backups if you have the capability to upload.