No. Cascade Pro is a single one-time purchase — pay once and every trick, lesson and pattern is yours, with no recurring fees. The first tricks, their lessons and the practice log are free.
Tap Restore purchase on the Pro screen or in Settings while signed into the same Apple Account. Apple restores your purchase; you will not be charged again.
Turn on Count catches with the camera in Settings, prop your iPhone up so it can see you and your props, and juggle. Cascade counts each catch and ends the run when you drop. Good light, a plain background and keeping your whole pattern in frame help it count accurately. Video is analysed on your iPhone and is never recorded or uploaded.
Check that Cascade has camera access in iOS Settings › Privacy & Security › Camera, step back so your hands and props are fully visible, and try brighter, even lighting. If counting still misses catches, you can always log the run by hand.
Make sure Daily reminder is on in Cascade's Settings and that notifications are allowed for Cascade in iOS Settings. The reminder is skipped on days you've already practised.
On your iPhone only — Cascade has no accounts and no servers. You can export your practice log as a CSV file from Settings › Your data. See the Privacy Policy for details.
Use Settings › Reset all progress. This erases your practice log and mastered tricks; your Pro purchase is not affected.
Siteswap is a number notation for juggling patterns — 3 is the three-ball cascade, 441 and 531 are classic tricks. Cascade's animator shows any valid pattern in motion so you can see the throws before you try them.