If you want an app that lets you customize the look of the story with different fonts and backgrounds, StoryScape AI could be for you. This storytelling app uses AI to generate immersive stories that can be read at different font sizes and with different backgrounds. You can start with a first chapter by filling in a few details about the story, and the app will generate an immersive experience with controls to steer the story in different directions.
Another option is DreamCanvas, which turns photos you upload into characters and stories. The AI-powered tool lets you customize character traits and dialogue, and it's got an AI Imagery Creation feature that can help tell your story with original imagery. DreamCanvas' free creation model means you can make as many books as you like with no initial cost, so it's good for personalized storytelling.
If you want to create illustrated children's stories, OnceUponABot is worth a look. The service uses the GPT-3 and Stable Diffusion AI models to generate stories you can customize with different reading levels and narrators. You can also edit and export your stories in different formats, too, which makes it good for parents, teachers and language learners.