Your firmware will be automatically updated whenever there is a new release.
However, should your firmware update stall and not complete, try placing your Spire back on the charging pad and restarting the app. After syncing to your Spire, any missed firmware update should begin downloading with a screen message indicating that "Magic is being added to your stone."
Should this not work, please try the following:
1. Uninstall the Spire App.
2. Reboot your Phone.
3. Reinstall the Spire app from App Store. Make sure that your Spire is on the charging pad.
Also, having your phone connected to a wi-fi network will help with the downloading of the firmware.