First, you need to select a cell on the grid. When a cell is selected, it will have a different background color than the others and so will its intersecting row and column. The keypad keys are highlighted to reflect the selected cell's current value.
When a cell is selected, you can input or modify its value by toggling the appropriate number key on the keypad. Toggling the currently highlighted key will erase that number from the cell. Toggling another number key sets that number.
The notes (pencil) key is special and toggles "notes mode" on and off. When on, you can select multiple number keys and they will all be noted in the cell. You can toggle these on and off as needed. When you are ready to enter an actual number, you toggle the notes key off and select the appropriate number key.
The notes key can be configured to apply to the selected cell only or to be sticky as you move to an empty cell. The default is sticky. This can be modified in the settings menu.
Undo and redo
At any time, you can undo and redo operations. On the iPad, the undo/redo buttons are located next to the menu button. On the iPhone, you need to select the back-arrow next to the menu button to reveal the undo/redo bar at the bottom of the screen.
From the menu, you can auto-compute and clear notes, reset the grid, or toggle various optional settings. You can also switch active "grid" if you want to work on more than one sudoku puzzle at the same time.
By default, the app highlights certain cells as a visual aid. Cells containing the last number entered are highlighted in blue. A group of two or more conflicting cells or an error will be highlighted in red. These optional visual aids can be toggled on and off in the settings menu.
Sudoku⁺ is designed to work alongside your iPod music app. You can exit the app at any time to start, stop, or manage your music. When you come back, it will be like you never left!
The quickest way to get to the iPod app is to double click the home button to bring up the multitasking bar. Swipe that once to the right to reveal your iPod controls.
These optional settings can all be configured from the menu.
- Highlight all cells containing the last selected number.
- Same as above but also in cells containing notes.
- Highlight conflicting cells containing the last selected number.
- Highlight all errors in the grid.
- Compute on New
- Automatically compute notes when generating new grids.
- When a number is entered in a cell, clear all its notes in the associated row, column, and box.
- Sticky Note Key
- Note key stays on when moving to an empty cell.
- Preserve on Clear
- Do not erase notes content of a cell when deselecting its note key.
- Promote on Clear
- Deselecting the note key in a single note cell promotes that note to a big number.
- Double-Tap Promote
- Quickly double tap a cell with a single note to promote that note to a big number.
- Show or hide the timer.
- Key Dots
- Show or hide the keypad dots. For each key, these dots indicate which boxes that number is set in.
- Bold Digits
- Use a bold font for all grid digits.
- Landscape Invert (iPad)
- Swap the keypad and grid in landscape mode.
- Full Screen (iPad)
- Toggle between full screen and retro layout.
- Grid Hovering
- Controls the ability to move around the grid when selecting a cell. When off, the first cell touched is selected. When on, the last cell touched is selected.
- Number then Cell
- When on, pressing a key while no cell is selected will enter number-then-cell mode. The key will remain lit. In this mode, selecting an empty cell automatically assigns it the lit key number. To exit this mode, toggle the key until it is no longer lit. When off, you cannot enter number-then-cell mode.
Is there a way to know when I have made an error?
The "Errors" highlight setting will do just that. This setting is off by default.
What are those dots in each number key?
The dots indicate which boxes in the grid a particular number is set in. This visual aid is optional and can be switched off in the settings menu.