The Little Writer app is so customizable! Today, I added our word of the day, "chair" and other words I use that start with "ch" and recorded my voice saying the ch words. I selected capital letters only, but I could have easily chosen all lower case, or even first letter capitalized and the rest lowercase. The app lets you add your own image too. What I appreciate is that each letter name is spoken before the child traces it and than the word is spoken after the all the letters are completed.
Writing Wizard by L'escapadou
Books:
There's a Bear on My Chair by Ross Collins
Meeow and the Little Chairs by Sebastian Braun
Song:
"Dancing Bear" by Bari Koral