TaskBook is a useful tool to control your to do tasks.
You can easily organize your tasks using tab and drag & drop.

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Functions to input tasks
There are functions to;
-input multiple tasks efficiently.
-collect tasks from paste board (clip board) input task list that you created with a Mac or a PC.
-attach a photo.
-attach a voice memo.

Functions to organize tasks
There are functions to;
-classify tasks using drag and drop. You classify tasks by dragging them to the "Do" list, the "Planned" list or the "Pending" list.
-order tasks by priority using drag and drop.
-sort task list by priority, state of task, color and date.
-tagging tasks.
-register events to calendar app.

Functions to complete tasks
There are functions to;
-show checklist. (hide tab and show check box.)
-check completed tasks with one touch.