You can try any of the following fonts for curly characters: calligraphic, fraktur, blackboard bold.
Here is an example:
\documentclass{article}\usepackage{amsmath}\usepackage{amssymb}\begin{document}$\mathcal{APPLE}$ $\mathfrak{APPLE}$ $\mathbb{APPLE}$ \end{document}
\documentclass{article}
\usepackage{amsmath}
\usepackage{amssymb}
\begin{document}
$\mathcal{APPLE}$
$\mathfrak{APPLE}$
$\mathbb{APPLE}$
\end{document}
source