What ShiftTrainer Trains
ShiftTrainer is a focused practice tool for the shift calculation used in a memorized-deck ACAAN handling. Version 1 uses Mnemonica.
The goal is to make the complete mental chain fast and dependable:
Named card → Mnemonica position → named position → shift calculation → card at the shift position
ShiftTrainer assumes you already know Mnemonica. It does not include a full stack reference table.
Reading a Problem
- The playing card is the spectator's named card.
- Position is the spectator's named target position from 1 to 52.
- Calculate the shift between the card's Mnemonica position and the named position.
- Find the Mnemonica card at that shift position.
- Answer What card do you cut at? by choosing its rank and suit.
Rank and suit can be selected in either order. Your answer submits automatically as soon as both are selected.
The Shift Calculation
Let C be the Mnemonica position of the named card and N be the named target position. Shift-zero problems are not used.
| Situation | Calculation |
|---|---|
| Card position is greater than named position | Shift = C − N |
| Named position is greater than card position | Difference = N − C Shift = 52 − Difference |
Example 1: 9♠ is #9 in Mnemonica and the named position is 1. Calculate 9 − 1 = 8. The card at #8 is 5♥, so the correct cut card is 5♥.
Example 2: 5♦ is #25 and the named position is 37. Calculate 37 − 25 = 12, then 52 − 12 = 40. The card at #40 is 4♠, so the correct cut card is 4♠.
Practice
Practice is pressure-free: there is no timer, score, accuracy, average, or streak.
- Correct answer: the selection turns green and a new random problem appears after half a second.
- Wrong answer: the selection turns red, the prompt stays visible, and the app shows the correct cut card with the complete arithmetic. Tap Next when you are ready.
10-Shift Challenge
Solve 10 shift problems correctly as quickly as possible.
- The timer begins the moment the first problem appears.
- A wrong answer does not advance. Keep trying the same problem while the timer continues.
- The timer stops immediately when the 10th problem is answered correctly.
- Results show total time, average seconds per shift, errors, and whether you set a personal best.
- Your best total time is stored locally on the device.
Frequently Asked Questions
Why am I choosing a card instead of entering a number?
The numeric shift is an intermediate step. The operational answer needed in performance is the Mnemonica card at the shift position — the card you cut at.
Can a problem have a shift of zero?
No. If the card's Mnemonica position and the named position are equal, ShiftTrainer discards that problem and generates another. Every other shift, including 51, is valid.
Does the app collect personal data?
No accounts, no tracking, no ads. The personal-best time stays on your device. See the Privacy Policy for details.
The app isn't working correctly. What should I do?
Please email [email protected] with a description of the issue, your device model, and iOS version. Screenshots are helpful.
About
ShiftTrainer is made by Kevin Haggard — magician, Mnemonica enthusiast, and creator of DeckClocker, SherlockTrainer, and QuartetTrainer.
Visit Magic Apps for more.