Stalla Flash Cards

Anyone use them before? I made my own for L1 but it got so messy and inconsistent Id like to purchase a set this time. Is it possible to purchase them only, or need to sign up for the entire program? The website doesn’t seem to clear on that? Thanks!

i saw Stalla Flash cards app on Apple’s appstore for iphone, Ipad, ipod touch. If you can get the hard copies, maybe you can consider this version