Legal Question in Technology Law in Alabama

Use "Book App" to your own peril. The addition or deletion of the word "the" will be immaterial in an infringement lawsuit. Trademark lawsuits are really driven by consumer confusion. Does the current app target the same industry as what you hope to target? Does the current app target the same geography as what you hope to target?

Further, if you choose a mark that is "merely descriptive" of your products you will not be able to obtain a federal trademark registration unless you have 5 years' of evidence proving that consumers identify your products with the name "Book App".

Keep in mind that before you start a company you do not have any investment in the "good will" of your mark and can make it anything you like. The name is not what your first customers will be buying and is also not what will have customers return. The name is what one happy customer will tell a friend to download so they get the same experience. Make it interesting, easy to remember, and, more than anything, unique.