Fabric books also known as Busy Books for toddlers are a great hit during travel. They also also known as Travel book for toddlers.
We at Scrapbookist, makes no sew quiet books for 2-4 years age and the longevity of these books are such that they can be passed on to next generations and would still be intact.
In this growing age of your kid, it is important for them to have some quiet time to themselves and use that time exploring new things, ideas etc. What better that their very own Quiet Book. The activities involved could be sorting colours, making puzzles, tying knots, shoe laces, learning fruits, shapes etc.
The skills that develop using these Quiet books are fine motor skills, problem solving, eye-hand coordination, attention, logical thinking, etc.
Though it is great idea to make your own Quiet Book if you have time, patience, some basic skills. However, if you are just too busy, go right above and buy one for your toddler.