Yes, after your card is flashed, insert it into a desktop computer and use any partition resizing tool you like. On Ubuntu, you would use the "gparted" program.
I looked a while back into doing this automatically when JeVois boots up, but it seems that the required utility (fatresize) has been deprecated for various reasons.
If you flash your card using the JeVois SDK and jevois-flash-card, the JEVOIS partition on the card will automatically use all available space.