Vocalist - Vocalist is an all-in-one music utility.
Overleaf - The online platform for scientific writing. Overleaf is free: start writing now with one click. No sign-up required. Great on your iPad.
Singscope - See your pitch analyzed as you sing
TeXworks - The TeXworks project is an effort to build a simple TeX front-end program (working environment)...
La-Vocal - Automate vocal exercises to practice easily & efficiently.
TeXstudio - TeXstudio is an integrated environment for writing LaTeX documents.